Did it work before?
Do all calls fail?
Can you receive calls?
Can you send/receive texts and use data?
Did anything change?
New phone, software update, settings changes etc.?
What make and model of phone is it?
Can you try your SIM in another unlocked phone temporarily just to see if the SIM is ok?
If necessary contact 48 support.
See the link in my signature below or email them at support@48months.zendesk.com
