diff --git a/common/transport/mqtt/src/main/java/org/thingsboard/server/transport/mqtt/MqttTransportHandler.java b/common/transport/mqtt/src/main/java/org/thingsboard/server/transport/mqtt/MqttTransportHandler.java
index abb8f629f1..bfd32eb751 100644
--- a/common/transport/mqtt/src/main/java/org/thingsboard/server/transport/mqtt/MqttTransportHandler.java
+++ b/common/transport/mqtt/src/main/java/org/thingsboard/server/transport/mqtt/MqttTransportHandler.java
@@ -357,37 +357,37 @@ public class MqttTransportHandler extends ChannelInboundHandlerAdapter implement
         log.info("[{}] Processing connect msg for client: {}!", sessionId, msg.payload().clientIdentifier());
         X509Certificate cert;
         if (sslHandler != null && (cert = getX509Certificate()) != null) {
-            processX509CertConnect(ctx, cert);
+            processX509CertConnect(ctx, cert, msg);
         } else {
             processAuthTokenConnect(ctx, msg);
         }
     }
 
-    private void processAuthTokenConnect(ChannelHandlerContext ctx, MqttConnectMessage msg) {
-        String userName = msg.payload().userName();
+    private void processAuthTokenConnect(ChannelHandlerContext ctx, MqttConnectMessage connectMessage) {
+        String userName = connectMessage.payload().userName();
         log.info("[{}] Processing connect msg for client with user name: {}!", sessionId, userName);
         if (StringUtils.isEmpty(userName)) {
-            ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_REFUSED_BAD_USER_NAME_OR_PASSWORD));
+            ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_REFUSED_BAD_USER_NAME_OR_PASSWORD, connectMessage));
             ctx.close();
         } else {
             transportService.process(ValidateDeviceTokenRequestMsg.newBuilder().setToken(userName).build(),
                     new TransportServiceCallback<ValidateDeviceCredentialsResponseMsg>() {
                         @Override
                         public void onSuccess(ValidateDeviceCredentialsResponseMsg msg) {
-                            onValidateDeviceResponse(msg, ctx);
+                            onValidateDeviceResponse(msg, ctx, connectMessage);
                         }
 
                         @Override
                         public void onError(Throwable e) {
                             log.trace("[{}] Failed to process credentials: {}", address, userName, e);
-                            ctx.writeAndFlush(createMqttConnAckMsg(MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE));
+                            ctx.writeAndFlush(createMqttConnAckMsg(MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE, connectMessage));
                             ctx.close();
                         }
                     });
         }
     }
 
-    private void processX509CertConnect(ChannelHandlerContext ctx, X509Certificate cert) {
+    private void processX509CertConnect(ChannelHandlerContext ctx, X509Certificate cert, MqttConnectMessage connectMessage) {
         try {
             if(!context.isSkipValidityCheckForClientCert()){
                 cert.checkValidity();
@@ -398,18 +398,18 @@ public class MqttTransportHandler extends ChannelInboundHandlerAdapter implement
                     new TransportServiceCallback<ValidateDeviceCredentialsResponseMsg>() {
                         @Override
                         public void onSuccess(ValidateDeviceCredentialsResponseMsg msg) {
-                            onValidateDeviceResponse(msg, ctx);
+                            onValidateDeviceResponse(msg, ctx, connectMessage);
                         }
 
                         @Override
                         public void onError(Throwable e) {
                             log.trace("[{}] Failed to process credentials: {}", address, sha3Hash, e);
-                            ctx.writeAndFlush(createMqttConnAckMsg(MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE));
+                            ctx.writeAndFlush(createMqttConnAckMsg(MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE, connectMessage));
                             ctx.close();
                         }
                     });
         } catch (Exception e) {
-            ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_REFUSED_NOT_AUTHORIZED));
+            ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_REFUSED_NOT_AUTHORIZED, connectMessage));
             ctx.close();
         }
     }
@@ -433,11 +433,11 @@ public class MqttTransportHandler extends ChannelInboundHandlerAdapter implement
         doDisconnect();
     }
 
-    private MqttConnAckMessage createMqttConnAckMsg(MqttConnectReturnCode returnCode) {
+    private MqttConnAckMessage createMqttConnAckMsg(MqttConnectReturnCode returnCode, MqttConnectMessage msg) {
         MqttFixedHeader mqttFixedHeader =
                 new MqttFixedHeader(CONNACK, false, AT_MOST_ONCE, false, 0);
         MqttConnAckVariableHeader mqttConnAckVariableHeader =
-                new MqttConnAckVariableHeader(returnCode, true);
+                new MqttConnAckVariableHeader(returnCode, !msg.variableHeader().isCleanSession());
         return new MqttConnAckMessage(mqttFixedHeader, mqttConnAckVariableHeader);
     }
 
@@ -513,9 +513,9 @@ public class MqttTransportHandler extends ChannelInboundHandlerAdapter implement
         }
     }
 
-    private void onValidateDeviceResponse(ValidateDeviceCredentialsResponseMsg msg, ChannelHandlerContext ctx) {
+    private void onValidateDeviceResponse(ValidateDeviceCredentialsResponseMsg msg, ChannelHandlerContext ctx, MqttConnectMessage connectMessage) {
         if (!msg.hasDeviceInfo()) {
-            ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_REFUSED_NOT_AUTHORIZED));
+            ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_REFUSED_NOT_AUTHORIZED, connectMessage));
             ctx.close();
         } else {
             deviceSessionCtx.setDeviceInfo(msg.getDeviceInfo());
@@ -532,17 +532,17 @@ public class MqttTransportHandler extends ChannelInboundHandlerAdapter implement
                     .build();
             transportService.process(sessionInfo, DefaultTransportService.getSessionEventMsg(SessionEvent.OPEN), new TransportServiceCallback<Void>() {
                 @Override
-                public void onSuccess(Void msg) {
+                public void onSuccess(Void response) {
                     transportService.registerAsyncSession(sessionInfo, MqttTransportHandler.this);
                     checkGatewaySession();
-                    ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_ACCEPTED));
+                    ctx.writeAndFlush(createMqttConnAckMsg(CONNECTION_ACCEPTED, connectMessage));
                     log.info("[{}] Client connected!", sessionId);
                 }
 
                 @Override
                 public void onError(Throwable e) {
                     log.warn("[{}] Failed to submit session event", sessionId, e);
-                    ctx.writeAndFlush(createMqttConnAckMsg(MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE));
+                    ctx.writeAndFlush(createMqttConnAckMsg(MqttConnectReturnCode.CONNECTION_REFUSED_SERVER_UNAVAILABLE, connectMessage));
                     ctx.close();
                 }
             });