E39 windows?

The window has lost itself. You need to teach it where the top is.

when you operate the window switch, you notice there are two positions separated by a slight click. You have to either hold the window switch for the full travel of the window on the first or second click. I forget which click you need, but only one of them will work, and the same one will work on the other window.

Hold the switch on the second click until the window is full up, then lower the window and test the Auto Up feature. If it does not work, then hold the switch on the first click and test again. Hold on the same position until the window has made all of the way to the top, and this will retrain it so that the Auto Up feature will work.