diff --git a/src/Models/Api/Client.php b/src/Models/Api/Client.php
index abe0814..360bbcf 100644
--- a/src/Models/Api/Client.php
+++ b/src/Models/Api/Client.php
@@ -8,6 +8,7 @@
 use GuzzleHttp\Exception\ConnectException;
 use GuzzleHttp\Exception\ServerException;
 use GuzzleHttp\RequestOptions;
+use Nette\Http\IResponse;
 use Nette\Utils\Json;
 use Tracy\Debugger;
 use Tracy\ILogger;
@@ -169,6 +170,12 @@ public function getMailLogs(?string $email, ?string $filter, ?int $limit, ?int $
                 $records[$i]->sent_at = new \DateTime($row->sent_at);
             }
             return $records;
+        } catch (ClientException $e) {
+            if ($e->getResponse()->getStatusCode() == IResponse::S400_BAD_REQUEST) {
+                Debugger::log($e, ILogger::ERROR);
+                return null;
+            }
+            throw $e;
         } catch (ServerException | ConnectException $e) {
             Debugger::log($e, ILogger::ERROR);
             return null;
@@ -195,6 +202,12 @@ public function countMailLogs(string $email, array $statuses, ?\DateTime $from,
             ]);
 
             return Json::decode($logsCount->getBody()->getContents(), true);
+        } catch (ClientException $e) {
+            if ($e->getResponse()->getStatusCode() == IResponse::S400_BAD_REQUEST) {
+                Debugger::log($e, ILogger::ERROR);
+                return null;
+            }
+            throw $e;
         } catch (ServerException | ConnectException $e) {
             Debugger::log($e, ILogger::ERROR);
             return null;
@@ -337,9 +350,13 @@ public function getUserPreferences($userId, $email, ?bool $subscribed = null)
 
             return Json::decode($result->getBody(), Json::FORCE_ARRAY);
         } catch (ClientException $e) {
-            if ($e->getResponse()->getStatusCode() == 404) {
+            if ($e->getResponse()->getStatusCode() == IResponse::S404_NOT_FOUND) {
                 return [];
             }
+            if ($e->getResponse()->getStatusCode() == IResponse::S400_BAD_REQUEST) {
+                Debugger::log($e, ILogger::ERROR);
+                return null;
+            }
             throw $e;
         } catch (ServerException | ConnectException $e) {
             Debugger::log($e, ILogger::ERROR);