diff --git a/paho_mqtt_embedded_c/MQTTClient/src/MQTTClient.h b/paho_mqtt_embedded_c/MQTTClient/src/MQTTClient.h
index 6afd927..5309f19 100644
--- a/paho_mqtt_embedded_c/MQTTClient/src/MQTTClient.h
+++ b/paho_mqtt_embedded_c/MQTTClient/src/MQTTClient.h
@@ -114,7 +114,6 @@ class Client
 {
 
 public:
-
     typedef void (*messageHandler)(MessageData&);
 
     /** Construct the client
@@ -234,10 +233,9 @@ class Client
     {
         return isconnected;
     }
-
-private:
-
     void closeSession();
+
+private:    
     void cleanSession();
     int cycle(Timer& timer);
     int waitfor(int packet_type, Timer& timer);
@@ -256,7 +254,9 @@ class Client
     unsigned char sendbuf[MAX_MQTT_PACKET_SIZE];
     unsigned char readbuf[MAX_MQTT_PACKET_SIZE];
 
-    Timer last_sent, last_received;
+    Timer last_sent;
+    Timer last_received;
+    Timer ping_sent;
     unsigned int keepAliveInterval;
     bool ping_outstanding;
     bool cleansession;
@@ -318,6 +318,9 @@ void MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::cleanSession()
 template<class Network, class Timer, int a, int MAX_MESSAGE_HANDLERS>
 void MQTT::Client<Network, Timer, a, MAX_MESSAGE_HANDLERS>::closeSession()
 {
+    last_sent.stop();
+    last_received.stop();
+    ping_sent.stop();
     ping_outstanding = false;
     isconnected = false;
     if (cleansession)
@@ -700,7 +703,6 @@ template<class Network, class Timer, int MAX_MQTT_PACKET_SIZE, int b>
 int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::keepalive()
 {
     int rc = SUCCESS;
-    static Timer ping_sent;
 
     if (keepAliveInterval == 0)
         goto exit;
@@ -1066,6 +1068,9 @@ int MQTT::Client<Network, Timer, MAX_MQTT_PACKET_SIZE, b>::disconnect()
     if (len > 0)
         rc = sendPacket(len, timer);            // send the disconnect packet
     closeSession();
+    last_sent.stop();
+    last_received.stop();
+    ping_sent.stop();
     return rc;
 }
 
diff --git a/paho_mqtt_embedded_c/MQTTClient/src/mbed/MQTTmbed.h b/paho_mqtt_embedded_c/MQTTClient/src/mbed/MQTTmbed.h
index 46f00e6..82c9492 100644
--- a/paho_mqtt_embedded_c/MQTTClient/src/mbed/MQTTmbed.h
+++ b/paho_mqtt_embedded_c/MQTTClient/src/mbed/MQTTmbed.h
@@ -36,7 +36,7 @@ class Countdown
 
     bool expired()
     {
-        return t.read_ms() >= interval_end_ms;
+        return (unsigned long)t.read_ms() >= interval_end_ms;
     }
 
     void countdown_ms(unsigned long ms)
@@ -57,6 +57,12 @@ class Countdown
         return interval_end_ms - t.read_ms();
     }
 
+    void stop()
+    {
+        t.stop();
+        t.reset();
+    }
+
 private:
     Timer t;
     unsigned long interval_end_ms;
diff --git a/src/MQTTClientMbedOs.cpp b/src/MQTTClientMbedOs.cpp
index 611e696..561d865 100644
--- a/src/MQTTClientMbedOs.cpp
+++ b/src/MQTTClientMbedOs.cpp
@@ -214,3 +214,8 @@ void MQTTClient::init(Socket *sock)
     client = NULL;
     clientSN = NULL;
 }
+
+void MQTTClient::mqttClientCloseSession()
+{
+    client->closeSession();
+}
diff --git a/src/MQTTClientMbedOs.h b/src/MQTTClientMbedOs.h
index a3459e6..81e16ea 100644
--- a/src/MQTTClientMbedOs.h
+++ b/src/MQTTClientMbedOs.h
@@ -22,7 +22,7 @@
 #include <TLSSocket.h>
 #include <DTLSSocket.h>
 #include <UDPSocket.h>
-#include "unity/unity.h"
+// #include "unity/unity.h"
 
 #include "FP.h"
 #include <MQTTPacket.h>
@@ -234,6 +234,8 @@ class MQTTClient {
      */
     nsapi_error_t setMessageHandler(const char *topicFilter, messageHandler mh);
 
+    void mqttClientCloseSession();
+
 private:
     /**
      * @brief Helper function to initialize member variables.