Sorry to be the first response and to be a bad one.
Are you able to connect to the celular network and call? It smell like bad EFS.
Go to Settings / About device / Status.
There look for IMEI and Serial number. If the serial no is 000... and thge imei is not the same as in the sticker behind the battery, its definitely caused by corrupt EFS.
Time for restoring your EFS (I hope you've done that before flashig anything!?)