I wonder if the window has lost its calibration. Check to see if the right rear window rolls all the way up if you pull the window switch up 2 clicks and then release. If it doesn't, there's a procedure for recalibrating:
1. Roll the window all the way down.
2. Roll the window all the up by pulling up 2 clicks and holding until it's closed.
3. Release the switch, then pull it up 2 clicks again and release.
I've had to do this a few times. Mostly it was after putting the doors back together after disconnecting the door electronics in order to install sound damping, but a couple of times windows have forgotten their calibration on their own.