Check in the phone settings that the network search is on automatic.
If you still do not have network coverage, it could be for two reasons:
- Hardware failure. You need technical support. Check the phone’s warranty prior to doing so.
- IMEI blocked. Call the network provider to confirm the phone’s IMEI has not been suspended due to loss, reported stolen or due to an unpaid bill.
To check if your phone is Blacklisted click on the link below: