Service method not calling second time

Question

I have two Interface one of which is a callback interface and one implementaion class as following.

[ServiceContract(CallbackContract = typeof(IMonitorCallback))]

interface IMonitor

{

   [OperationContract(IsOneWay = true)]

   Task AddMonitor(Monitor mo);

 

   [OperationContract(IsOneWay = true)]

   Task RemoveMonitor(Monitor mo);

}

interface IMonitorCallback

{

   [OperationContract]

   void OnAdded(Monitor data);

 

   [OperationContract]

   void OnRemoved(Monitor data);

}

[ServiceBehavior(ConcurrencyMode = ConcurrencyMode.Single, InstanceContextMode = InstanceContextMode.Single)]

public class Monitor : IMonitor

{

   public Task AddMonitor(Monitor mo)

   {}

   public Task RemoveMonitor(Monitor mo)

   {}

}

Now i want to call this method from unit test one after the another (in a single test method). I am able to call the AddMonitor but when i call the Remove method its not hitting the service method. Code is given below.

 

[TestClass]

public class Test

{

   private Monitor monitor = null;

   private IMonitor proxy = null;

   private DuplexChannelFactory<IMonitor> channelFactory;

   private ManualResetEvent mutex = new ManualResetEvent(false);

   // This class for callback implementation

   private MonitorCallback monitorCallback = null;

   public void TestInitialize()

   {

   this.monitor = new Monitor();

   // Hosting is done here

   this.monitor.Initialize();

   this.monitorCallback = new MonitorCallback();

   this.monitorCallback.OnDataValueChanged += () =>

   {

   if (null != this.valueChangedMutex)

   {

   this.valueChangedMutex.Set();

   }

  };

   this.channelFactory = new DuplexChannelFactory<IMonitor>(this.monitorCallback,

   new NetTcpBinding(),

   this.clientAddress);

   try

   {

   this.proxy = this.channelFactory.CreateChannel();

   }

   catch

   {

   if (null != proxy)

   {

   ((ICommunicationObject)proxy).Abort();

   this.proxy = null;

   }

   throw;

}

}

[TestMethod]

[TestCategory("StatusMonitor")]

public async Task TestRemoveMonitor()

{

 this.mutex.Reset();

 await this.proxy.AddMonitor(mo);

 this.mutex.WaitOne(30000);

 this.mutex.Reset();

 await this.proxy.RemoveMonitor(mo);

 this.mutex.WaitOne(10000);

}

}

Can someone provide me a solution for this.