Unlock - AT&T <=> Consumer Cellular

I was an AT&T customer for decades up until Sept of 2018 when we switched to Consuumer Cellular (with AT&T SIM)  as we are retiring and will use our phones less.

My wife has an iPhone 6 which we bought from AT&T long ago, and I am pretty sure we unlocked it a couple or several years ago when it became eligible.

My wife is a Kiwi and we travel to NZ regularly, swapping out NZ carrier SIMs with no problem.

This year, however, when I put in ANY NZ carrier SIM , it indicates that it is locked, is not an iPhone hardware problem, and to contact our carrier.

This same SIM worked in this same iPhone last March of 2018 when we came to NZ.

My iPhone 7 from AT&T has a similar history and has no problem accepting any SIM I put in it. When I put that SIM in the iPhone 6, it fails.

Although AT&T says "We're happy to unlock your phone whether a current customer or not!", I am not finding that to be the case in any direct fashion.

When I go to the AT&T auto-unlock site now, it takes the information, but indicates " Device you want to unlock is Active on another AT&T account. If you are the owner, call 800 331-0500 which will not permit me to talk to an agent, but routes me through an auto-unlock info routine that hangs up.

Another Discussion Board message suggests writing to @ATTCares, but when I follow the link, it says personal messages are no longer accepted and answered. Post in Community.

I called ConsumerCellular and they said that it was bought from AT&T so call AT&T, which I can't do without an account.

This is frustratingly convoluted to do all this from New Zealand.

I was under the impression that once an iPhone was purchased and unlocked, that was a permanent condition, and have never heard that using another SIM could re-lock it.

Also, with nearly identical histories (AT&T purchase, unlock, move to CCellular) , why does the iPhone7 work with all SIMS, and the iPhone6 now work with none?

So here I am. Is here anyone who can help me break this infinite loop of hopelessness?

I would rather do it through normal channels, but are there legitimate businesses that can break the unlock if required? I know if the original iPhone days I had to unlock an original iPhone that way.

Provide Contact suggestions, or ??

Help!

Bob *****

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