I had a bizarre incident last night where my iPhone6 suddenly displayed the keyboard in front of my key pad and said it was disabled, as I tried to enter the pin. I hadn’t tried the pin more than once.
It was right after I had walked into a movie theater and I wondered if the theater was blocking it. I was able to get rid of the problem simply leaving the auditorium for moment, turning off the phone, and then turning it back on again.
Using recovery mode looks very complicated and would not work if you were on a trip or on the road and not easily able to use a synced laptop. Here is a writeup.
You can go to an Apple store but typically the “Genius Bar” requires appointments.
I have had a problem with an unwanted iTunes sign in popping up, as well as iCloud siginons on my MacBook. The Apple store cleared it once, but it returned. I just now signed on to iCloud on a windows computer and that worked and send the usual 2-step verification code.
I also accidentally let the power go down yesterday, but had charged it back up before the incident.
The usual reason for a phone’s being disabled is signing on with the incorrect pin more than 6 times (source), which was not the case for me (unless there was a nearby hacker, or somehow the phone had banged into mechanically; I had stored the AMC movie ticket on the phone). . I got a “try again in one minute” message. It’s possible that time consumed in shutting down and rebooting simply caused the problem ti time out.