Well like ssteel said, photos and parts list would be helpful. Seems like the issue could be a lot of things but we are in the dark without more details/pics. If you cant muster that, then you are on your own. The issue could include one or more of the below (assuming we are talking about gen construction 16610 sub): The crystal gasket is too thick thereby expanding the retaining ring such that there is too much friction against the bezelThe bezel is bent due to inproper installationThe retaining ring could also be damaged/bentThe crystal diameter is too wide thereby expanding the gasket too much and thus creating problem already explained in point #1The retaining ring and bezel are not compatible with each other (if you matched a retaining ring from one manufacturer with a bezel from another, very good chance they will not mate properly)something else I am too tired to think about right now