diff --git a/src/interface.jl b/src/interface.jl
index c5cee00..40b342b 100644
--- a/src/interface.jl
+++ b/src/interface.jl
@@ -204,7 +204,7 @@ end
 """
 function mqttReconnect!(client::mqttClient)
     if client.connectStatus == false
-        Mosquitto.disconnect(client) # disconnect to release port before attemping new connection
+        Mosquitto.disconnect(client.clientInstance) # disconnect to release port before attemping new connection
 
         if client.userName === nothing    # check if the member needs username/password
             result = Mosquitto.connect(client.clientInstance, client.broker, client.port)
@@ -239,16 +239,26 @@ end
 """
     mqtt communication loop, call this function manually 
 """
-function mqttRun(client::mqttClient)
+function mqttRun(client::mqttClient, userMsgHandler::Function)
     mqttLoop!(client)
     mqttCheckConnection!(client)
     mqttReconnect!(client)
     mqttSubOnConnect!(client)
+    mqttOnmessage!(client, userMsgHandler)
 end
 
 
-# What to do if there is a message
-function mqttOnmessage!(client::mqttClient, msgHandler::Function)
+"""
+    userMsgHandler. A user defined function in user space.
+
+    # Example
+
+    function mqttMsgHander(topic::String, payload)
+        # this function access workSpace by global variable and do something with msg
+    end
+
+"""
+function mqttOnmessage!(client::mqttClient, userMsgHandler::Function)
     nmessages = Base.n_avail(get_messages_channel())
     nmessages == 0 && return 0
 
@@ -260,7 +270,7 @@ function mqttOnmessage!(client::mqttClient, msgHandler::Function)
             _ = take!(get_messages_channel()) # discard new arrival package
         end
     elseif timepass > 1 && client.retainedMsgCleared == false
-        workDict[:retainedMsgCleared] = true
+        client.retainedMsgCleared = true
         println("retained mqtt messages cleared")
     else
         for i = 1:nmessages
@@ -270,12 +280,14 @@ function mqttOnmessage!(client::mqttClient, msgHandler::Function)
             payload = vecToDict(pkg.payload)    # payload in Dict format
 
             # Do something with the message
-            msgHandler(topic, payload)
+            println("call userMsgHandler")
+            userMsgHandler(topic, payload)      # user defined function in user space. How to handle msg
         end
     end
 end 
 
 
+
 function publish(client::mqttClient, msg::Dict, pubtopic::String="")
     Mosquitto.publish(client.clientInstance, pubtopic, JSON3.write(msg))
 end
@@ -284,24 +296,6 @@ end
 """
     request function check msg for additional communication info in addition to publish()
 """
-# function request(client::mqttClient, msg::Dict; pubtopic::String="")
-#     if pubtopic != ""
-#         Mosquitto.publish(client.clientInstance, pubtopic, JSON3.write(msg))
-#     elseif  msg[:msgMeta][:sendto] != ""
-#         Mosquitto.publish(client.clientInstance, msg[:msgMeta][:sendto], JSON3.write(msg))
-#     else
-#         if length(client.pubtopic) != 0
-            
-#             for (k, topic) in pairs(client.pubtopic)
-#                 println("pub to $k")
-#                 Mosquitto.publish(client.clientInstance, topic, JSON3.write(msg))
-#             end
-#         else
-#             error("publish topic not defined")
-#         end
-#     end
-# end
-
 function request(client::mqttClient, msg::Dict; pubtopic::String="")
     pubto = Vector{String}()
     if pubtopic != ""