Service not closing gracefully.

We downloaded the sample code from " https://github.com/Azure/AzureAD-BYOA-Provisioning-Samples/tree/master" and compiled them. We are using the sample which maintains a file with comma separated values representing users and groups. The service application is execute in our server, we enabled the Port 9000 for Inbound and listening. Every thing works fine but when we press any key for closing the service, the program closes all the ports and the server instance on AWS goes to non reachable mode. Can we have a Stop method before disposing the "Service" object.