diff --git a/database/migrations/create_subscription_tables.php.stub b/database/migrations/create_subscription_tables.php.stub
index 9e10fe1..b5d1f17 100644
--- a/database/migrations/create_subscription_tables.php.stub
+++ b/database/migrations/create_subscription_tables.php.stub
@@ -28,7 +28,7 @@ class CreateSubscriptionTables extends Migration
          */
         Schema::create('dk_subscriptions', function (Blueprint $table) {
             $table->bigIncrements('id');
-            $table->unsignedBigInteger('user_id');
+            $table->unsignedBigInteger(app(config('paystacksubscription.model'))->getForeignKey());
             $table->string('name');
             $table->string('paystack_id')->unique();
             $table->string('paystack_status');
@@ -39,7 +39,7 @@ class CreateSubscriptionTables extends Migration
             $table->timestamp('ends_at')->nullable();
             $table->timestamps();
 
-            $table->index(['user_id', 'paystack_status']);
+            $table->index([app(config('paystacksubscription.model'))->getForeignKey(), 'paystack_status']);
         });
     }
 
diff --git a/src/SubscriptionBuilder.php b/src/SubscriptionBuilder.php
index 89463a0..8eed20a 100644
--- a/src/SubscriptionBuilder.php
+++ b/src/SubscriptionBuilder.php
@@ -1,199 +1,214 @@
 <?php
 
 
-    namespace Digikraaft\PaystackSubscription;
+namespace Digikraaft\PaystackSubscription;
+
+use Carbon\Carbon;
+use Digikraaft\Paystack\Paystack;
+use Digikraaft\Paystack\Plan;
+use Digikraaft\Paystack\Subscription as PaystackSubscription;
+use Digikraaft\Paystack\Transaction;
+use Digikraaft\PaystackSubscription\Exceptions\PaymentFailure;
+use Digikraaft\PaystackSubscription\Exceptions\SubscriptionUpdateFailure;
+use Illuminate\Support\Facades\Log;
+
+class SubscriptionBuilder
+{
+
+    /**
+     * The model that is subscribing.
+     *
+     * @var \Illuminate\Database\Eloquent\Model
+     */
+    protected $owner;
+
+    /**
+     * The name of the subscription.
+     *
+     * @var string
+     */
+    protected string $name;
+
+    /**
+     * The ID or Code of the plan being subscribed to.
+     *
+     * @var string
+     */
+    protected string $plan;
+
+    /**
+     * The authorization code used to create subscription.
+     *
+     * @var string
+     */
+    protected string $authorization;
+
+    /**
+     * Create a new subscription builder instance.
+     *
+     * @param  mixed  $owner
+     * @param  string  $name
+     * @param  string  $plan
+     * @return void
+     */
+    public function __construct($owner, $name, $plan)
+    {
+        $this->owner = $owner;
+        $this->name = $name;
+        $this->plan = $plan;
+    }
 
-    use Digikraaft\Paystack\Paystack;
-    use Digikraaft\Paystack\Plan;
-    use Digikraaft\Paystack\Subscription as PaystackSubscription;
-    use Digikraaft\Paystack\Transaction;
-    use Digikraaft\PaystackSubscription\Exceptions\PaymentFailure;
-    use Digikraaft\PaystackSubscription\Exceptions\SubscriptionUpdateFailure;
+    /**
+     * Add a new Paystack subscription to the Paystack model.
+     *
+     * @param string|null $authorization
+     * @param string $transactionId
+     * @param array $customerOptions
+     * @return \Digikraaft\PaystackSubscription\Subscription
+     * @throws \Digikraaft\PaystackSubscription\Exceptions\PaymentFailure
+     */
+    public function add(string $transactionId = null, string $authorization = null, array $customerOptions = [])
+    {
+        return $this->create($transactionId, $authorization, $customerOptions);
+    }
 
-    class SubscriptionBuilder
+    /**
+     * Create a new Paystack subscription.
+     *
+     * @param string|null $authorization
+     * @param string|null $transactionId
+     * @param array $customerOptions
+     * @return \Digikraaft\PaystackSubscription\Subscription
+     *
+     * @throws Exceptions\PaymentFailure
+     */
+    public function create(string $transactionId = null, string $authorization = null, array $customerOptions = [])
     {
+        $customer = $this->getPaystackCustomer($customerOptions);
 
-        /**
-         * The model that is subscribing.
-         *
-         * @var \Illuminate\Database\Eloquent\Model
-         */
-        protected $owner;
-
-        /**
-         * The name of the subscription.
-         *
-         * @var string
-         */
-        protected string $name;
-
-        /**
-         * The ID or Code of the plan being subscribed to.
-         *
-         * @var string
-         */
-        protected string $plan;
-
-        /**
-         * The authorization code used to create subscription.
-         *
-         * @var string
-         */
-        protected string $authorization;
-
-        /**
-         * Create a new subscription builder instance.
-         *
-         * @param  mixed  $owner
-         * @param  string  $name
-         * @param  string  $plan
-         * @return void
-         */
-        public function __construct($owner, $name, $plan)
-        {
-            $this->owner = $owner;
-            $this->name = $name;
-            $this->plan = $plan;
+        if (is_null($authorization)) {
+            $paystackSubscription = $this->createSubscriptionFromTransaction($transactionId, $customer);
+        } else {
+            $paystackSubscription = $this->createSubscriptionFromAuthorization($authorization, $customer);
         }
 
-        /**
-         * Add a new Paystack subscription to the Paystack model.
-         *
-         * @param string|null $authorization
-         * @param string $transactionId
-         * @param array $customerOptions
-         * @return \Digikraaft\PaystackSubscription\Subscription
-         * @throws \Digikraaft\PaystackSubscription\Exceptions\PaymentFailure
-         */
-        public function add(string $transactionId = null, string $authorization = null, array $customerOptions = [])
-        {
-            return $this->create($transactionId, $authorization, $customerOptions);
-        }
+        // save authorization to owner
+        $this->owner->paystack_authorization = $paystackSubscription->authorization->authorization_code;
+        $this->authorization = $paystackSubscription->authorization->authorization_code;
+        $this->owner->save();
+
+
+        //retrieve plan code
+        $plan = Plan::fetch($paystackSubscription->plan->id);
+
+        /** @var \Digikraaft\PaystackSubscription\Subscription $subscription */
+        $subscription = Subscription::create([
+            'name' => $this->name,
+            'paystack_id' => $paystackSubscription->subscription_code,
+            'paystack_status' => $paystackSubscription->status,
+            'paystack_plan' => $plan->data->plan_code,
+            'quantity' => $paystackSubscription->quantity ?? '1',
+            'email_token' => $paystackSubscription->email_token,
+            'authorization' => $this->authorization,
+            'ends_at' => Carbon::parse($paystackSubscription->next_payment_date),
+            app(config('paystacksubscription.model'))->getForeignKey() => $this->owner->id,
+        ]);
+
+        return $subscription;
+    }
 
-        /**
-         * Create a new Paystack subscription.
-         *
-         * @param string|null $authorization
-         * @param string|null $transactionId
-         * @param array $customerOptions
-         * @return \Digikraaft\PaystackSubscription\Subscription
-         *
-         * @throws Exceptions\PaymentFailure
-         */
-        public function create(string $transactionId = null, string $authorization = null, array $customerOptions = [])
-        {
-            $customer = $this->getPaystackCustomer($customerOptions);
-
-            if (is_null($authorization)) {
-                $paystackSubscription = $this->createSubscriptionFromTransaction($transactionId, $customer);
-            } else {
-                $paystackSubscription = $this->createSubscriptionFromAuthorization($authorization, $customer);
-                $this->authorization = $paystackSubscription->authorization;
-            }
-
-            // save authorization to owner
-            $this->owner->paystack_authorization = $paystackSubscription->authorization->authorization_code;
-            $this->owner->save();
-
-
-            //retrieve plan code
-            $plan = Plan::fetch($paystackSubscription->plan->id);
-
-            /** @var \Digikraaft\PaystackSubscription\Subscription $subscription */
-            $subscription = Subscription::create([
-                'name' => $this->name,
-                'paystack_id' => $paystackSubscription->subscription_code,
-                'paystack_status' => $paystackSubscription->status,
-                'paystack_plan' => $plan->data->plan_code,
-                'quantity' => $paystackSubscription->quantity ?? '1',
-                'email_token' => $paystackSubscription->email_token,
-                'authorization' => $this->authorization,
-                'ends_at' => $paystackSubscription->next_payment_date,
-                'user_id' => $this->owner->id,
-            ]);
-
-//        return dd("sssse3");
-
-            return $subscription;
-        }
+    /**
+     * Get the Paystack customer instance for the current user and payment method.
+     *
+     * @param  array  $options
+     * @return \Digikraaft\Paystack\Customer
+     */
+    protected function getPaystackCustomer(array $options = [])
+    {
+        return $this->owner->createOrGetPaystackCustomer($options);
+    }
 
-        /**
-         * Get the Paystack customer instance for the current user and payment method.
-         *
-         * @param  array  $options
-         * @return \Digikraaft\Paystack\Customer
-         */
-        protected function getPaystackCustomer(array $options = [])
-        {
-            return $this->owner->createOrGetPaystackCustomer($options);
-        }
+    /**
+     * Create a new Paystack subscription using authorization code.
+     *
+     * @param string|null $authorization
+     * @param $customer
+     * @return \Digikraaft\PaystackSubscription\Subscription
+     */
+    protected function createSubscriptionFromAuthorization(string $authorization, $customer)
+    {
+        $payload = array_merge(
+            ['customer' => $customer->data->customer_code],
+            ['authorization' => $authorization],
+            ['plan' => $this->plan],
+        );
 
-        /**
-         * Create a new Paystack subscription using authorization code.
-         *
-         * @param string|null $authorization
-         * @param $customer
-         * @return \Digikraaft\PaystackSubscription\Subscription
-         */
-        protected function createSubscriptionFromAuthorization(string $authorization, $customer)
-        {
-            $payload = array_merge(
-                ['customer' => $customer->data->customer_code],
-                ['authorization' => $authorization],
-                ['plan' => $this->plan],
-            );
+        Paystack::setApiKey(config('paystacksubscription.secret', env('PAYSTACK_SECRET')));
 
-            Paystack::setApiKey(config('paystacksubscription.secret', env('PAYSTACK_SECRET')));
+        try {
 
             return PaystackSubscription::create(
                 $payload,
             )->data;
-        }
 
-        /**
-         * Create a new Paystack subscription using transaction reference.
-         *
-         * @param string $transactionId
-         * @param $customer
-         * @return \Digikraaft\PaystackSubscription\Subscription
-         * @throws \Digikraaft\PaystackSubscription\Exceptions\PaymentFailure
-         * @throws SubscriptionUpdateFailure
-         */
-        protected function createSubscriptionFromTransaction(string $transactionId, $customer)
-        {
-            //verify from Paystack that the transaction was successful
-            Paystack::setApiKey(config('paystacksubscription.secret', env('PAYSTACK_SECRET')));
-            $transaction = Transaction::fetch($transactionId);
-            if (! $transaction->status || $transaction->data->status != 'success') {
-                throw PaymentFailure::incompleteTransaction($transaction);
-            }
-
-            if ($transaction->data->plan->plan_code != $this->plan) {
-                throw PaymentFailure::invalidTransactionPlan($transaction, $this->plan);
-            }
-
-            if ($transaction->data->customer->customer_code != $customer->data->customer_code) {
-                throw SubscriptionUpdateFailure::invalidCustomer();
-            }
-
-
-
-            //check if user is already subscribed to plan. This is to guard against multiple subscriptions with the same transactionId
-            if ($this->owner->subscribedToPlan($transaction->data->plan->plan_code)) {
-                throw SubscriptionUpdateFailure::duplicateSubscription($this->owner, $transaction->data->plan->name);
-            }
-
-            $this->authorization = $transaction->data->authorization->authorization_code;
+        } catch (\Exception $exception) {
 
             $paystackSubscription = \Digikraaft\Paystack\Subscription::list(
                 [
                     'perPage' => 1,
                     'page' => 1,
-                    'customer' => $transaction->data->customer->id,
-                    'plan' => $transaction->data->plan->id,
+                    'customer' => $customer->data->id,
                 ]
             );
 
             return $paystackSubscription->data->{0};
         }
     }
+
+    /**
+     * Create a new Paystack subscription using transaction reference.
+     *
+     * @param string $transactionId
+     * @param $customer
+     * @return \Digikraaft\PaystackSubscription\Subscription
+     * @throws \Digikraaft\PaystackSubscription\Exceptions\PaymentFailure
+     * @throws SubscriptionUpdateFailure
+     */
+    protected function createSubscriptionFromTransaction(string $transactionId, $customer)
+    {
+        //verify from Paystack that the transaction was successful
+        Paystack::setApiKey(config('paystacksubscription.secret', env('PAYSTACK_SECRET')));
+
+        $transaction = Transaction::fetch($transactionId);
+
+        if (! $transaction->status || $transaction->data->status != 'success') {
+            throw PaymentFailure::incompleteTransaction($transaction);
+        }
+
+        if ($transaction->data->plan->plan_code != $this->plan) {
+            throw PaymentFailure::invalidTransactionPlan($transaction, $this->plan);
+        }
+
+        if ($transaction->data->customer->customer_code != $customer->data->customer_code) {
+            throw SubscriptionUpdateFailure::invalidCustomer();
+        }
+
+        //check if user is already subscribed to plan. This is to guard against multiple subscriptions with the same transactionId
+        if ($this->owner->subscribedToPlan($transaction->data->plan->plan_code)) {
+            throw SubscriptionUpdateFailure::duplicateSubscription($this->owner, $transaction->data->plan->name);
+        }
+
+        $this->authorization = $transaction->data->authorization->authorization_code;
+
+        $paystackSubscription = \Digikraaft\Paystack\Subscription::list(
+            [
+                'perPage' => 1,
+                'page' => 1,
+                'customer' => $transaction->data->customer->id,
+                'plan' => $transaction->data->plan->id,
+            ]
+        );
+
+        return $paystackSubscription->data->{0};
+    }
+}
diff --git a/src/Traits/ManagesCustomer.php b/src/Traits/ManagesCustomer.php
index 50a20c7..e68493c 100644
--- a/src/Traits/ManagesCustomer.php
+++ b/src/Traits/ManagesCustomer.php
@@ -27,7 +27,7 @@ public function paystackId()
      */
     public function hasPaystackId()
     {
-        return ! is_null($this->paystack_id);
+        return ! (is_null($this->paystackId()) || $this->paystackId() == '');
     }
 
     /**
@@ -57,7 +57,7 @@ public function paystackAuthorization()
      *
      * @throws \Digikraaft\PaystackSubscription\Exceptions\InvalidCustomer
      */
-    protected function assertCustomerExists()
+    protected function assertCustomerExists(): void
     {
         if (! $this->hasPaystackId()) {
             throw InvalidCustomer::doesNotExist($this);
@@ -72,7 +72,7 @@ protected function assertCustomerExists()
      *
      * @throws \Digikraaft\PaystackSubscription\Exceptions\CustomerAlreadyExist
      */
-    public function createAsPaystackCustomer(array $options = [])
+    public function createAsPaystackCustomer(array $options = []): PaystackCustomer
     {
         if ($this->hasPaystackId()) {
             throw CustomerAlreadyExist::exists($this);
@@ -117,9 +117,9 @@ public function updatePaystackCustomer(array $options = [])
      *
      * @param array $options
      * @return \Digikraaft\Paystack\Customer
-     * @throws \Digikraaft\PaystackSubscription\Exceptions\InvalidCustomer
+     * @throws \Digikraaft\PaystackSubscription\Exceptions\InvalidCustomer|CustomerAlreadyExist
      */
-    public function createOrGetPaystackCustomer(array $options = [])
+    public function createOrGetPaystackCustomer(array $options = []): PaystackCustomer
     {
         if ($this->hasPaystackId()) {
             return $this->asPaystackCustomer();
@@ -131,7 +131,7 @@ public function createOrGetPaystackCustomer(array $options = [])
     /**
      * Get the Paystack customer for the model.
      *
-     * @return \Digikraaft\Paystack\Customer
+     * @return array|object
      * @throws \Digikraaft\PaystackSubscription\Exceptions\InvalidCustomer
      */
     public function asPaystackCustomer()
@@ -149,7 +149,7 @@ public function asPaystackCustomer()
      *
      * @return string|null
      */
-    public function paystackEmail()
+    public function paystackEmail(): ?string
     {
         return $this->email;
     }