I don't know why the "AP" is causing that to be flagged as an error during the Federal review if it was entered correctly in the mailing address. Did you use a different mailing address when entering some other form in the return?
I'll see if I can get one of the TurboTax experts to comment in this thread later this morning. Some are usually in the forum starting around about 6-7 AM Central.
If you don't get a response today, here's another option. TurboTax does not offer support via email. You said you couldn't reach TurboTax Support by phone. Do you have Facebook or X (Twitter)? If so, here's how to reach a TurboTax Support agent with messaging during business hours.
Currently 7 days a week 5am-9pm (PST) this time of year.
https://x.com/TeamTurboTax
or
https://www.facebook.com/turbotax
