GYYR Timelapse recorder problem

Play mode will not take up tape. Tape loads to head and continues
feeding tape into unit but not winding on the take-up side (or whatever
you call it). I replaced a stretched square belt on the take-up side,
still have same problem. My brain wants to tell me it's a mechanical
issue, but....... I want to ask before I put my mitts on it.

Thanks:

Bill