Unlock device after switching AT&T accounts (paid off)

Hi,

Here is the issue I'm having....

I was on a AT&T family account paying on an installment plan for an iPhone 7, the phone was paid off prior to switching to a new cell phone plan (still with AT&T). I've tried submitting the unlock request multiple times with no success saying the IMEI doesn't match the phone on the account.

I went into the AT&T store, the guy couldn't really figure it out either... he switched the IMEI from my mother's phone (who is still on the family plan I was on with my 7) and still was not able to submit the request.

Help...