When you delete a CommonLit assignment on Canvas, we don't delete the assignment on CommonLit. As a result, you may receive an error that the assignment is already assigned because it still exists in CommonLit.
If you would like to re-link the CommonLit assignment to Canvas, go to your class's Assignments page and click the Dashboard button.
On your Assignment Dashboard Page, click the Unlink Assignment button below the Canvas icon.
Once you've unlinked the assignment, you will be able to re-link it on Canvas.
Alternatively, if you would like to reassign a completely new assignment, go to your class's Assignments page. Then click the trash can icon on the top right of your assignment to delete your assignment. Once you've deleted the assignment, you will be able to reassign it to your class.