When was it working ok last?
Did anything change on your phone in the meantime?
E.g. phone software update, settings changes, factory reset/restore, new phone handset, returned from roaming abroad, etc.?
Do incoming calls, incoming/outgoing texts, mobile data work?
Do you have an active membership plan?
Have you tried reseating the SIM in case it somehow got dislodged?
If you need to contact 48 support about this then see the links in my signature below.
