System.IO.IOException: Unable to read data from the transport connection

I recieve following error in my windows service after running it certain hours of time.

Windows service is calling a webservice url every 30 seconds. Lets i have retrieved 500 rows from db and looped through it and is calling my webservice to again save back the data.  

 I am making httpwebrequest in middle and getting response.  Post getting response i m again logging to db by calling a web service method. After running few hours of time fine i get this error.

The underlying connection was closed: An unexpected error occurred on a receive. System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. ---> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host

Any help will be appreciated. 

 
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