Help! Polaris 300 explorer goes into gear but acts like its in neautral

Anybody have any idea what could be wrong with my polaris. I was riding my polaris 300 explorer and the chain come off causing an sudden stop. I got the chain back on, and now it will do nothing, acts like its in neutral, it will change gears on lyncage, but does nothing. The clutch and belt seem to be in good shape and working correctly.