diff --git a/bridge/go.mod b/bridge/go.mod
index 36df4c94f..a7e7f4ac8 100644
--- a/bridge/go.mod
+++ b/bridge/go.mod
@@ -62,7 +62,7 @@ require (
 	github.com/x-cray/logrus-prefixed-formatter v0.5.2 // indirect
 	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
 	golang.org/x/crypto v0.11.0 // indirect
-	golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 // indirect
+	golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d // indirect
 	golang.org/x/net v0.12.0 // indirect
 	golang.org/x/sys v0.12.0 // indirect
 	golang.org/x/term v0.12.0 // indirect
diff --git a/common/storage/local/sqlite.go b/common/storage/local/sqlite.go
index 48cf8d39d..9a9849650 100644
--- a/common/storage/local/sqlite.go
+++ b/common/storage/local/sqlite.go
@@ -86,6 +86,10 @@ const createPingHistory string = `
   updated_at DATETIME NOT NULL                                                  
   );`
 
+const createPingHistoryUniqueIndex string = `
+CREATE UNIQUE INDEX IF NOT EXISTS ping_history_unique ON ping_history(supernode_id, ip_address);
+`
+
 const (
 	historyDBName = "history.db"
 	emptyString   = ""
@@ -188,8 +192,8 @@ func (s *SQLiteStore) UpsertPingHistory(pingInfo types.PingInfo) error {
 			is_online = excluded.is_online,
 			is_on_watchlist = excluded.is_on_watchlist,
 			is_adjusted = excluded.is_adjusted,
-		    last_seen = excluded.last_seen
-		    cumulative_response_time = excluded.cumulative_response_time
+		    last_seen = excluded.last_seen,
+		    cumulative_response_time = excluded.cumulative_response_time,
 			updated_at = excluded.updated_at;`
 
 	_, err := s.db.Exec(upsertQuery,
@@ -207,7 +211,7 @@ func (s *SQLiteStore) UpsertPingHistory(pingInfo types.PingInfo) error {
 func (s *SQLiteStore) GetPingInfoBySupernodeID(supernodeID string) (*types.PingInfo, error) {
 	const selectQuery = `
         SELECT id, supernode_id, ip_address, total_pings, total_successful_pings,
-               avg_ping_response_time, is_online, is_on_watchlist, is_adjusted, last_seen,
+               avg_ping_response_time, is_online, is_on_watchlist, is_adjusted, last_seen, cumulative_response_time,
                created_at, updated_at
         FROM ping_history
         WHERE supernode_id = ?;`
@@ -219,7 +223,7 @@ func (s *SQLiteStore) GetPingInfoBySupernodeID(supernodeID string) (*types.PingI
 	err := row.Scan(
 		&pingInfo.ID, &pingInfo.SupernodeID, &pingInfo.IPAddress, &pingInfo.TotalPings,
 		&pingInfo.TotalSuccessfulPings, &pingInfo.AvgPingResponseTime,
-		&pingInfo.IsOnline, &pingInfo.IsOnWatchlist, &pingInfo.IsAdjusted, &pingInfo.LastSeen,
+		&pingInfo.IsOnline, &pingInfo.IsOnWatchlist, &pingInfo.IsAdjusted, &pingInfo.LastSeen, &pingInfo.CumulativeResponseTime,
 		&pingInfo.CreatedAt, &pingInfo.UpdatedAt,
 	)
 
@@ -234,7 +238,7 @@ func (s *SQLiteStore) GetPingInfoBySupernodeID(supernodeID string) (*types.PingI
 func (s *SQLiteStore) GetWatchlistPingInfo() ([]types.PingInfo, error) {
 	const selectQuery = `
         SELECT id, supernode_id, ip_address, total_pings, total_successful_pings,
-               avg_ping_response_time, is_online, is_on_watchlist, is_adjusted, last_seen,
+               avg_ping_response_time, is_online, is_on_watchlist, is_adjusted, last_seen, cumulative_response_time,
                created_at, updated_at
         FROM ping_history
         WHERE is_on_watchlist = true AND is_adjusted = false;`
@@ -251,7 +255,7 @@ func (s *SQLiteStore) GetWatchlistPingInfo() ([]types.PingInfo, error) {
 		if err := rows.Scan(
 			&pingInfo.ID, &pingInfo.SupernodeID, &pingInfo.IPAddress, &pingInfo.TotalPings,
 			&pingInfo.TotalSuccessfulPings, &pingInfo.AvgPingResponseTime,
-			&pingInfo.IsOnline, &pingInfo.IsOnWatchlist, &pingInfo.IsAdjusted, &pingInfo.LastSeen,
+			&pingInfo.IsOnline, &pingInfo.IsOnWatchlist, &pingInfo.IsAdjusted, &pingInfo.LastSeen, &pingInfo.CumulativeResponseTime,
 			&pingInfo.CreatedAt, &pingInfo.UpdatedAt,
 		); err != nil {
 			return nil, err
@@ -362,7 +366,7 @@ func (s *SQLiteStore) InsertSelfHealingChallenge(challenge types.SelfHealingChal
 func (s *SQLiteStore) GetAllPingInfos() (types.PingInfos, error) {
 	const selectQuery = `
         SELECT id, supernode_id, ip_address, total_pings, total_successful_pings,
-               avg_ping_response_time, is_online, is_on_watchlist, is_adjusted, last_seen,
+               avg_ping_response_time, is_online, is_on_watchlist, is_adjusted, last_seen, cumulative_response_time,
                created_at, updated_at
         FROM ping_history
         `
@@ -379,7 +383,7 @@ func (s *SQLiteStore) GetAllPingInfos() (types.PingInfos, error) {
 		if err := rows.Scan(
 			&pingInfo.ID, &pingInfo.SupernodeID, &pingInfo.IPAddress, &pingInfo.TotalPings,
 			&pingInfo.TotalSuccessfulPings, &pingInfo.AvgPingResponseTime,
-			&pingInfo.IsOnline, &pingInfo.IsOnWatchlist, &pingInfo.IsAdjusted, &pingInfo.LastSeen,
+			&pingInfo.IsOnline, &pingInfo.IsOnWatchlist, &pingInfo.IsAdjusted, &pingInfo.LastSeen, &pingInfo.CumulativeResponseTime,
 			&pingInfo.CreatedAt, &pingInfo.UpdatedAt,
 		); err != nil {
 			return nil, err
@@ -433,6 +437,10 @@ func OpenHistoryDB() (storage.LocalStoreInterface, error) {
 		return nil, fmt.Errorf("cannot create table(s): %w", err)
 	}
 
+	if _, err := db.Exec(createPingHistoryUniqueIndex); err != nil {
+		return nil, fmt.Errorf("cannot create table(s): %w", err)
+	}
+
 	_, _ = db.Exec(alterTaskHistory)
 
 	pragmas := []string{
diff --git a/common/types/self_healing.go b/common/types/self_healing.go
index 323a894cd..1aa4fcede 100644
--- a/common/types/self_healing.go
+++ b/common/types/self_healing.go
@@ -44,7 +44,7 @@ type PingInfo struct {
 	LastSeen               sql.NullTime `db:"last_seen"`
 	CreatedAt              time.Time    `db:"created_at"`
 	UpdatedAt              time.Time    `db:"updated_at"`
-	LastResponseTime       float64
+	LastResponseTime       float64      `db:"-"`
 }
 
 // PingInfos represents array of ping info
diff --git a/mixins/go.mod b/mixins/go.mod
index 7c288f5d5..56bbb5614 100644
--- a/mixins/go.mod
+++ b/mixins/go.mod
@@ -41,7 +41,7 @@ require (
 	github.com/stretchr/testify v1.8.4 // indirect
 	github.com/x-cray/logrus-prefixed-formatter v0.5.2 // indirect
 	golang.org/x/crypto v0.11.0 // indirect
-	golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 // indirect
+	golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d // indirect
 	golang.org/x/sync v0.3.0 // indirect
 	golang.org/x/sys v0.12.0 // indirect
 	golang.org/x/term v0.12.0 // indirect
diff --git a/supernode/node/grpc/server/services/supernode/self_healing.go b/supernode/node/grpc/server/services/supernode/self_healing.go
index 321e7eb9b..5acde9b79 100644
--- a/supernode/node/grpc/server/services/supernode/self_healing.go
+++ b/supernode/node/grpc/server/services/supernode/self_healing.go
@@ -93,8 +93,6 @@ func (service *SelfHealingChallengeGRPC) Desc() *grpc.ServiceDesc {
 
 // Ping is the server side of self-healing challenge processing GRPC comms
 func (service *SelfHealingChallengeGRPC) Ping(ctx context.Context, pingReq *pb.PingRequest) (*pb.PingResponse, error) {
-	log.WithContext(ctx).WithField("req", pingReq).Info("ping request received at the server side")
-
 	task := service.NewSHTask()
 	res, err := task.Ping(ctx, pingReq)
 	if err != nil {
diff --git a/supernode/services/common/reg_task_helper.go b/supernode/services/common/reg_task_helper.go
index 6966eeb16..88b9ba048 100644
--- a/supernode/services/common/reg_task_helper.go
+++ b/supernode/services/common/reg_task_helper.go
@@ -248,9 +248,9 @@ func (h *RegTaskHelper) verifyTxn(ctx context.Context,
 	txn *pastel.GetRawTransactionVerbose1Result, totalAmt float64, percent float64) error {
 	inRange := func(val float64, reqVal float64, slackPercent float64) bool {
 		lower := reqVal - (reqVal * slackPercent / 100)
-		upper := reqVal + (reqVal * slackPercent / 100)
+		//upper := reqVal + (reqVal * slackPercent / 100)
 
-		return val >= lower && val <= upper
+		return val >= lower
 	}
 
 	log.WithContext(ctx).Debug("Verifying Burn Txn")
diff --git a/supernode/services/selfhealing/generate_self_healing.go b/supernode/services/selfhealing/generate_self_healing.go
index ff7cd6f90..f945e3e31 100644
--- a/supernode/services/selfhealing/generate_self_healing.go
+++ b/supernode/services/selfhealing/generate_self_healing.go
@@ -73,7 +73,7 @@ func (task *SHTask) GenerateSelfHealingChallenge(ctx context.Context) error {
 	selfHealingTicketsMap := task.identifySelfHealingTickets(ctx, watchlistPingInfos, mapOfClosestNodesAgainstKeys, symbolFileKeyMap)
 	log.WithContext(ctx).WithField("self_healing_tickets", selfHealingTicketsMap).Info("self-healing tickets have been identified")
 
-	challengeRecipientMap, err := task.identifyChallengeRecipients(ctx, selfHealingTicketsMap)
+	challengeRecipientMap, err := task.identifyChallengeRecipients(ctx, selfHealingTicketsMap, watchlistPingInfos)
 	if err != nil {
 		log.WithContext(ctx).WithError(err).Error("error identifying challenge recipients")
 	}
@@ -287,7 +287,7 @@ func (task *SHTask) isOnWatchlist(nodeID string, watchlistPingInfos types.PingIn
 	return false
 }
 
-func (task *SHTask) identifyChallengeRecipients(ctx context.Context, selfHealingTicketsMap map[string]SymbolFileKeyDetails) (map[string][]SymbolFileKeyDetails, error) {
+func (task *SHTask) identifyChallengeRecipients(ctx context.Context, selfHealingTicketsMap map[string]SymbolFileKeyDetails, watchlist types.PingInfos) (map[string][]SymbolFileKeyDetails, error) {
 	challengeRecipientMap := make(map[string][]SymbolFileKeyDetails)
 	for txID, ticketDetails := range selfHealingTicketsMap {
 		logger := log.WithContext(ctx).WithField("TxID", txID)
@@ -309,7 +309,7 @@ func (task *SHTask) identifyChallengeRecipients(ctx context.Context, selfHealing
 			logger.WithError(err).Error("unable to retrieve list of supernodes")
 		}
 
-		challengeRecipients := task.SHService.GetNClosestSupernodeIDsToComparisonString(ctx, 1, string(dataHash), listOfSupernodes)
+		challengeRecipients := task.SHService.GetNClosestSupernodeIDsToComparisonString(ctx, 1, string(dataHash), task.filterWatchlistAndCurrentNode(watchlist, listOfSupernodes))
 		if len(challengeRecipients) < 1 {
 			log.WithContext(ctx).WithField("file_hash", dataHash).Info("no closest nodes have found against the file")
 			continue
@@ -621,3 +621,21 @@ func (service *SHService) getListOfSupernode(ctx context.Context) ([]string, err
 
 	return ret, nil
 }
+
+func (task *SHTask) filterWatchlistAndCurrentNode(watchList types.PingInfos, listOfSupernodes []string) []string {
+	var filteredList []string
+
+	for _, nodeID := range listOfSupernodes {
+		if task.isOnWatchlist(nodeID, watchList) {
+			continue
+		}
+
+		if task.nodeID == nodeID {
+			continue
+		}
+
+		filteredList = append(filteredList, nodeID)
+	}
+
+	return filteredList
+}
diff --git a/supernode/services/selfhealing/ping_nodes.go b/supernode/services/selfhealing/ping_nodes.go
index c0e65fb56..1ce0f7416 100644
--- a/supernode/services/selfhealing/ping_nodes.go
+++ b/supernode/services/selfhealing/ping_nodes.go
@@ -48,8 +48,11 @@ func (task *SHTask) getNodesAddressesToConnect(ctx context.Context) ([]pastel.Ma
 	for _, mn := range supernodes {
 		if mn.ExtAddress == "" || mn.ExtKey == "" {
 			log.WithContext(ctx).WithField("method", "FetchAndMaintainPingInfo").
-				WithField("node_id", mn.ExtKey).Warn("node address or node id is empty")
+				WithField("node_id", mn.ExtKey).Debug("node address or node id is empty")
+			continue
+		}
 
+		if mn.ExtKey == task.nodeID {
 			continue
 		}
 
@@ -81,7 +84,7 @@ func (task *SHTask) pingNodes(ctx context.Context, nodesToPing pastel.MasterNode
 			res, err := task.ping(ctx, req, node.ExtAddress)
 			if err != nil {
 				log.WithContext(ctx).WithField("sn_address", node.ExtAddress).WithError(err).
-					Error("error pinging sn")
+					Debug("error pinging sn")
 
 				pi := types.PingInfo{
 					SupernodeID:      node.ExtKey,
@@ -91,27 +94,29 @@ func (task *SHTask) pingNodes(ctx context.Context, nodesToPing pastel.MasterNode
 				}
 
 				if err := task.StorePingInfo(ctx, pi); err != nil {
-					log.WithContext(ctx).WithError(err).Error("error storing ping info")
+					log.WithContext(ctx).WithField("supernode_id", pi.SupernodeID).
+						WithError(err).
+						Error("error storing ping info")
 				}
 
 				return
 			}
 
-			respondedAt, err := time.Parse(UTCTimeLayout, res.RespondedAt)
-			if err != nil {
-				log.WithContext(ctx).WithError(err)
-			}
+			lastSeen := time.Now().UTC()
+			responseTime := lastSeen.Sub(timeBeforePing).Abs().Seconds()
 
 			pi := types.PingInfo{
 				SupernodeID:      node.ExtKey,
 				IPAddress:        node.ExtAddress,
 				IsOnline:         res.IsOnline,
-				LastResponseTime: respondedAt.Sub(timeBeforePing).Seconds(),
-				LastSeen:         sql.NullTime{Time: respondedAt, Valid: true},
+				LastSeen:         sql.NullTime{Time: lastSeen, Valid: true},
+				LastResponseTime: responseTime,
 			}
 
 			if err := task.StorePingInfo(ctx, pi); err != nil {
-				log.WithContext(ctx).WithError(err).Error("error storing ping info")
+				log.WithContext(ctx).WithField("supernode_id", pi.SupernodeID).
+					WithError(err).
+					Error("error storing ping info")
 			}
 		}()
 	}
@@ -123,7 +128,7 @@ func (task *SHTask) pingNodes(ctx context.Context, nodesToPing pastel.MasterNode
 
 // ping just pings the given node address
 func (task *SHTask) ping(ctx context.Context, req *pb.PingRequest, supernodeAddr string) (*pb.PingResponse, error) {
-	log.WithContext(ctx).Info("pinging supernode: " + supernodeAddr)
+	log.WithContext(ctx).Debug("pinging supernode: " + supernodeAddr)
 
 	// Create a context with timeout
 	pingCtx, cancel := context.WithTimeout(ctx, timeoutDuration)
@@ -133,7 +138,6 @@ func (task *SHTask) ping(ctx context.Context, req *pb.PingRequest, supernodeAddr
 	nodeClientConn, err := task.nodeClient.Connect(pingCtx, supernodeAddr)
 	if err != nil {
 		err = fmt.Errorf("could not use node client to connect to: %s, error: %v", supernodeAddr, err)
-		log.WithContext(ctx).Warn(err.Error())
 		return nil, err
 	}
 	defer nodeClientConn.Close()
@@ -212,6 +216,10 @@ func (task *SHTask) GetPingInfoFromDB(ctx context.Context, supernodeID string) (
 
 			return nil, err
 		}
+
+		if info == nil {
+			return &types.PingInfo{}, nil
+		}
 	}
 
 	return info, nil
@@ -225,7 +233,7 @@ func GetPingInfoToInsert(existedInfo, info *types.PingInfo) *types.PingInfo {
 
 	info.TotalPings = existedInfo.TotalPings + 1
 
-	if !existedInfo.LastSeen.Valid { //for the first row
+	if existedInfo.LastSeen.Time.IsZero() || !(existedInfo.LastSeen.Valid) { //for the first row
 		info.LastSeen = sql.NullTime{Time: time.Now().UTC(), Valid: true}
 	}
 
@@ -237,9 +245,14 @@ func GetPingInfoToInsert(existedInfo, info *types.PingInfo) *types.PingInfo {
 
 	if !info.IsOnline {
 		info.TotalSuccessfulPings = existedInfo.TotalSuccessfulPings
-		info.LastSeen = existedInfo.LastSeen
 		info.IsOnWatchlist = existedInfo.IsOnWatchlist
 		info.IsAdjusted = existedInfo.IsAdjusted
+
+		if existedInfo.LastSeen.Time.IsZero() || !(existedInfo.LastSeen.Valid) { //for the first row
+			info.LastSeen = sql.NullTime{Time: time.Now().UTC(), Valid: true}
+		} else {
+			info.LastSeen = existedInfo.LastSeen
+		}
 	}
 
 	info.CumulativeResponseTime = existedInfo.CumulativeResponseTime + info.LastResponseTime
diff --git a/supernode/services/selfhealing/ping_nodes_test.go b/supernode/services/selfhealing/ping_nodes_test.go
index 62a10c805..125cbadda 100644
--- a/supernode/services/selfhealing/ping_nodes_test.go
+++ b/supernode/services/selfhealing/ping_nodes_test.go
@@ -22,9 +22,9 @@ func TestGetInfoToInsert(t *testing.T) {
 	}{
 		{
 			testCase:     "when node is offline, should increment total ping only",
-			existedInfo:  &types.PingInfo{TotalPings: 2, TotalSuccessfulPings: 2},
+			existedInfo:  &types.PingInfo{TotalPings: 2, TotalSuccessfulPings: 2, LastSeen: sql.NullTime{Time: now, Valid: true}},
 			receivedInfo: &types.PingInfo{TotalPings: 0, IsOnline: false},
-			expectedInfo: &types.PingInfo{TotalPings: 3, TotalSuccessfulPings: 2, IsOnline: false},
+			expectedInfo: &types.PingInfo{TotalPings: 3, TotalSuccessfulPings: 2, IsOnline: false, LastSeen: sql.NullTime{Time: now, Valid: true}},
 		},
 		{
 			testCase:     "when node is online, should increment total ping & total successful pings",
diff --git a/supernode/services/selfhealing/process_ping.go b/supernode/services/selfhealing/process_ping.go
index 216e9129e..6f582a322 100644
--- a/supernode/services/selfhealing/process_ping.go
+++ b/supernode/services/selfhealing/process_ping.go
@@ -10,7 +10,7 @@ import (
 
 // Ping acknowledges the received message and return with the timestamp
 func (task *SHTask) Ping(ctx context.Context, _ *pb.PingRequest) (*pb.PingResponse, error) {
-	log.WithContext(ctx).WithField("node_id", task.nodeID).Println("ping request received at the server")
+	log.WithContext(ctx).WithField("node_id", task.nodeID).Debug("ping request received at the server")
 
 	return &pb.PingResponse{
 		ReceiverId:  task.nodeID,
diff --git a/supernode/services/selfhealing/service.go b/supernode/services/selfhealing/service.go
index bca2a1abd..15f3e4917 100644
--- a/supernode/services/selfhealing/service.go
+++ b/supernode/services/selfhealing/service.go
@@ -101,9 +101,9 @@ func (service *SHService) Run(ctx context.Context) error {
 	for {
 		select {
 		case <-time.After(defaultTimerBlockCheckDuration):
-			newCtx := context.Background()
-			task := service.NewSHTask()
-			task.GenerateSelfHealingChallenge(newCtx)
+			//newCtx := context.Background()
+			//task := service.NewSHTask()
+			//task.GenerateSelfHealingChallenge(newCtx)
 
 			log.WithContext(ctx).Debug("Would normally invoke a self-healing worker")
 		case <-ctx.Done():
diff --git a/supernode/services/selfhealing/update_watchlist.go b/supernode/services/selfhealing/update_watchlist.go
index a0801b45e..d40677b91 100644
--- a/supernode/services/selfhealing/update_watchlist.go
+++ b/supernode/services/selfhealing/update_watchlist.go
@@ -25,6 +25,7 @@ func (task *SHTask) UpdateWatchlist(ctx context.Context) error {
 			info.IsOnWatchlist = true
 			info.IsAdjusted = false
 
+			log.WithContext(ctx).WithField("supernode_id", info.SupernodeID).Info("updating watchlist flag")
 			if err := task.UpsertPingHistory(ctx, info); err != nil {
 				log.WithContext(ctx).
 					WithField("supernode_id", info.SupernodeID).