BMW 320i electric windows working intermittently

My electric windowns on my BMW 320i stopped working recently when i was trying to get the drivers side window to free up a bit as it was a bit stiff. All windows and the sunroof didnt work for 2 weeks then without notice they started working again. This only lasted 2 days and now they have stopped working again. All fuses are fine and im wondering if it could be something to do with the safety feature.