I used to program the opening time of ours to not be right at sunrise, due to a bobcat stalking in the morning; I’d notice it slightly changing time, over time too - I think it’s because its open/close function is a timer paired with the daylight hours, not based off a clock.
Other than that I haven’t really had any issues. This year I noticed the door not closing all the way leaving a slight gap at the bottom. Upon investigation there was dirt/mud caked at the bottom of the door track. Must have been a slow accumulation because if the door hits an object in the doorway it will stop and reverse motion. The “stop” for the motor is hitting the end of the track, so if you have the motor off the door it will essentially keep going until it hits resistance to simulate the end of the track
At that same time I cleaned the track I decided to swap the 2yr old batteries haha. Then the door was acting weird and not opening properly - which was magically resolved by taking the batteries out for more than 2min, per Run Chickens advice.
I’m 5yrs now into using ours, we still love it, great purchase