c#中调用Web服务的非托管泄漏

我需要帮助我的代码。

我一直在尝试使用RedGate来监控我的应用程序的内存使用情况，经过几个小时的测试，它指出了我的应用程序的非托管代码，我只能认为我的web服务调用是我的代码中唯一或有些非托管的部分。我调试了几个小时，似乎找不到哪里或什么真正发生了。下面是我的代码。

private void btnstart_Click(object sender, EventArgs e)
{
    btnPressed = !btnPressed //boolean
    if(btnPressed)
    {
        myTask = Task.Factory.StartNew(() => 
        {
            do {
                _checkMatches(token.Token);
            } while (token.IsCancellationRequested != true);
        },token.Token);
    }
    else
    {
        token.Cancel();
        try {
            Task.WaitAny(myTask);
        }
        catch(Exception Error) {
            //Put to logs
        }
        finally
        {
            if(myTask.isCancelled || myTask.IsCompleted || myTask.IsFaulted)
            {
                myTask.Dispose();
            } 
        }
    }
}
private void _checkMatches(CancellationToken token) 
{
    try
    {
        if(token.IsCancellationRequested)
        {
            token.ThrowIfCancellationRequested();
        }
        EndpointAddressBuilder ServiceEndPoint = new EndpointAddressBuilder(//Read Endpoint From Notepad);
        ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(delegate { return true; });//just bypassing validation for test purposes
        // WebService is an ASMX web service
        using (WebService.SoapClient client = new WebService.SoapClient()) 
        {
            WebService.checkResponse clientRes = client.checkClient();
            if(clientRes.response == 1 || clientRes.response == 2) {
                //Put to Logs
            }
        }
    }
    catch(Exception error){
        //Put to logs
    }
}