update

src/communication.jl

@@ -156,6 +156,7 @@ function mqttClientInstance_v2(
     keepaliveCheckInterval::Integer=30,
     qos::MQTTClient.QOS=QOS_1,
     multiMsg::String="single",
+    clearOldMsg::Bool=true,
   )
   
   client, connection = MQTTClient.MakeConnection(mqttBrokerAddress, mqttBrokerPort)
@@ -182,6 +183,15 @@ function mqttClientInstance_v2(
     nothing,  # store latest message to prevent doing the same massage twice
   )
 
+  if clearOldMsg
+    chnames = keys(msgReceiveChannel)
+    for i in chnames
+      while isready(msgReceiveChannel[i])
+        _ = take!(msgReceiveChannel[i])
+      end
+    end
+  end
+
   return instance
 end