I have cleaned the tray. I have replaced the sim today for another virgin Sim. I am getting the same issues. I notice it occurs when the phone loses signal and goes in "emergency calls only" mode. A message then comes up on the phone that says New sim inserted restart phone. This does not happen with other network providers.
I am tempted to go to ofcom and file a complaint as I am not getting the level of service expected. There is clearly an issue with virgin mobile.
From what you've explained, due to the SIM card working in another handset, the issue does not lie with the SIM card or the network. If it did, that SIM card would replicate the same problem in whatever handset you placed it in.
Is the handset damaged at all from what you can see?
I understand, but if the SIM card and network works fine in another handset then the SIM and network won't be at fault as the fault would replicate regardless of handset. If the issue only happens in that handset then it's likely that the handset itself is at fault and struggling to recognise the SIM card and/or network.
Can you confirm roughly when you purchased the handset and where/who you purchased it from?