Dude! I'm having a senior moment, but I also had a window that went in one direction. My problem turned out to be a screw that had come out and a bushing kind of thingy had broken.

I was expecting to find a broken window regulator, but what I discovered was that a plastic bit was broken. I was able to swap the same part from another location that I decided would tolerate the repaired part better than repairing the part and putting it back into the original location. In this diagram, I think my troubles came from the Item 7, CLIP.

I had to remove the window from the regulator, and then I tested the regulator with the switch and it went both ways. As I remember, I took the window regulator out of the car and plugged it in to test. I expected to find the cable unwound and kinked, but it was all good. The Item 7 was in one of the mounting locations, but not in the other, so I looked inside of the door and found it. I tried to fix it with a washer and a collar. but it didn't work. Then without any warning, the piece reappeared from having been lodged somewhere. I fixed the window without buying anything.

https://www.realoem.com/bmw/enUS/sho...diagId=51_3896