Happened to me. I have a J1772 charger with the NACS adapter on it. I normally press the physical disconnect charger button on the handle and then quickly re-engage it and pull out the entire handle plus adapter in the small window of time this creates. However, for some reason this time the port did not unlock. I think it may have been due to the Bluetooth key somehow not being seen by the car.
At any rate, this is when the port door simply would not open, even tho I was able to unlock the adapter from the in car console. I had to manually pull the door open to put the charger back in, and the door continually tried to close regardless of the charger being in and would not stay open, etc.
Luckily, I simply went to sleep on it and the problem appeared to have resolved itself in the morning. Definitely a software bug of some sort. I suspect fiddling with the charger while the car and Bluetooth key thought they were not in proximity caused the issue.