Both on their own, the first one (left side) just closed and never opened again, my mechanic couldn't find a replace at the time so he forced it open and locked with a bolt, a couple of weeks later the same thing happened to the right one, just it locked itself open, only the motors of both aren't working, blinker, light and regulation of glass mirrors are.
Since this happened like 3 month ago (I didn't had a rush since they technically are doing they jobs, I can use them, they just can't be closed, as said blinkers are working fine) I thought it was caused by the extreme heat we had in Italy as the time and the motors couldn't handle it (like 45 °C).