I don’t know how to fix it, it is the third time i use blender but that never happened to me,how i fix it?
(i was fixing the model with CATS and that happened)
The Blender developers do not maintain this add-on, any bugs or errors should be reported to the author of the add-on.
Bugs in Blender also should not be reported on this forum, but rather in the bug tracker:
https://developer.blender.org/maniphest/task/edit/form/1/