Happend to me once. Yes I manually folded back in and got itself corrected with buttom after that. No problem since. I was afraid I was gonna end up with mirror on my hand but was able to fix it. Not sure what happened, probably my wife or daughter hit it in the garage.
I fold mine in all the time and sometimes I hear a squicking noise coming from mirrors. I added a bit of WD-40 just to help and it did. I will do it again once I hear noise. Maybe I should not use them all the time I dont want them to brak on me. I love this feature in my car. Cheeers!!