10-16-2019 5:25 PM
This has absolutely nothing to do with your cellular carrier. This is an Apple feature
10-16-2019 8:56 PM
Posting every 5 minutes isn’t going to result in anything happening. If your screen is locked and it’s asking for a passcode, follow the instructions that lizdance40 posted. If the phone is carrier locked and won’t work with non-AT&T SIMs, then use the unlocking portal. https://www.att.com/deviceunlock/#/unlockstep1
Asking again won’t provide different answers.
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