Clamping roller blocked! Reason for timing belt teeth abrasion???

Good evening together, I already opened a topic a few days ago (Audi broken 80 timing belts. Motor in the ass? HELP!!), tomorrow the ordered timing belt should come off today I noticed that the tensioning roller could not move a bit. It should do so, right? Could that have been the reason to block the tensioning roller for the abrasion of the timing belt teeth? The camshaft wheel can be easily however always cut (always ca n e 1/4 turn) but that’s correct, right? Does anyone else have a good tip for the timing belt exchange? I already have rough instructions. Thanks already for the answers.