Start your phone voice recorder anytime a manager wants to have a conversation with you about anything.
This is only as a CYA type of move - it is not to be done as a gotcha type of move. Many of the stupid a– insults that managers are hitting us with originate from NC not from your manager.
If you are written up you will have something to back up your situation. You may let your manager know if you want that you will be recording the conversation. If convo is legit they will haave no problem.