Really sorry to hear about this, @MrFresh. We’d love to help you out with this. In order to take a closer look, can you please send us a private message with your phone number, PIN, IMEI and ICCID (SIM card numbers) from your device?
To send a private message just click on the picture of any Virgin Mobile agent and, in the next screen, click "send this user a private message".
I have been having issues with my phone since December 2. My Samsung Galaxy J7 has been throwing me the SIM card locked followed by SIM card removed errors forcing mandatory restarts since then, making my phone unusable. But today it started showing me this Invalid SIM card error as well. My phone starts and has service for around 4 minutes then goes into SIM card is locked then followed by SIM card removed within 2 minutes that requires a restart, and then after the restart Invalid SIM card error.