[xeroinfinity]

Welcome to AF!

Sounds like the front seal is in the way, does it open all the way?
IF it does, look in the front of the tracks, the seal is a long black rubber part in front that touches the front of the glass(from underneeth), if the metal is bent up the glass will hit it and not close all the way in the back.

Other than that it would hav to be the tracks needing some grease, not much in the back of the glass to hold it open, just two rubber stopers, one on each side.

Hope this helps !!