The phone, however, was searching for service which is typical of a newly powered phone. Several minutes past and the service had still not connected. I powered the phone off and on again which will usually fix the problem.. yet still … no go.
I did a hard reset
Holding the power and home button continuously until the phone shuts down and reboots
I then powered it down, removed the SIM card and cleaned it thoroughly. I then re-installed, powered iPhone 5 back on.
Still no luck
I powered it off, then removed the battery and began examining the iPhone 5 for hardware problems which may have been caused during the screen replacement process.
Nevertheless, everything seemed in order.
I seated all cables and checked for tears or misalignment
I next paid close attention to the connectors and cables that are associated with 3G reception
there was no visible damage or misalignment
I reassembled and powered the iPhone 5 back up
then checked for SIM in the Settings>General>About
it was there and read the correct number
After calling AT&T support and speaking to the tech they said there is a phenomenon where SIM can be blacklisted from being removed and the iPhone detecting hardware change.
We were preparing for a OTA reset “over the air” reset … before we did that We re-set all settings and powered off device and the SIM alert “locked ” appeared I contacted the client and he gave me the password and moments after I entered it the service returned.
So ….Sometimes a Service can be locked or interrupted because of SIM removal and will require service provider assistance .
Thank You AT&T for your fantastic service and assistance