Phone was unlocked, but phone says it's network locked.

I have a LG V20 that was purchased through AT&T and paid off that was unlocked prior to an overseas move. The phone wasn't used for awhile before finally getting a new SIM card with another carrier; however, when plugging in the new SIM it says it it still "network locked".

Called customer service back in the states, and they said it was because the account was suspended after move that the phone wasn't actually unlocked. Rep said after un-suspending the account within 24-48hrs, I should be able to unlock. This wasn't the case as with plugging in the PUK number still didn't  unlock the phone.
With running through AT&T unlock site, it's listing the IMEI number is not listed as an AT&T device. Which isn't surprising since the phone should already be unlocked.

How am I supposed to unlock a phone that has already been unlocked?