It is really hard to get the problem from your description and without having any kind of error messages or code. But wild guess based on these information from you:

> self-signed certificate .... Nothing received at the end of the server.

Since the certificate is self-signed it would be normal that the connection failed because certificate validation failed (unless you add the certificate to the CA store or disable validation). Did you check that the connection succeeded? Because if it failed you would of course not get any data at the server side.