How to delete/undo imported assignments

Spchase
Community Novice

I am trying to delete imported assignments from under the assignments tab.  When I click on the 3 dots on the right, delete is gray out.  I also can not move the assignments to another group, the dots on the left are also grayed out.  Please advise - I need to do this so I can add weigh to my assignments.  It's not letting me do that either because I have assignments in a "closed course"....