More detail. The infinity end is glued using some better glue(dark material), while the close end is NOT.

The fix is

Mark or remember the position BEFORE removing two screws and contact brush! but relax, this part is not extremely precise.

Lift the PCB. Cleanup double sided tape. Glue the PCB back firmly against the inner edge.

Use proper glue, like "high viscous super glue" or "2-part epoxy resin". Do NOT use low viscous glue, it will mess up and contaminate the contacts.