Welcome to the forum and thanks for posting. Sorry to hear you're having signal issues and the network being unavailable.
I like to check something's from my end but I will require some further information from you. Due to the nature of the information I require I will send you a private message shortly (red envelope, top left hand side) to discuss this further.
I have the same problem. Virgin fobbed me off by blaming my SIM and sent me a new one which duly arrived. I phoned to activate it and now, 55 hrs later, I still have no network connection because it has not been activated. Or so they say. They lied about the activation time, and they lied about taking personal charge of the issue and promising to call me back.
I've posted a thread about this and no Virgin representative seems concerned enough to offer any help.