Geting a corrupt file message when trying to save file. Close file without saving and reopen to find that it had actually saved any changes that had been made. Closed and re-start software only to experience the same issue after a few times saving the document. Had the same issue with Indesign 2021 prior to upgrade. Issue went away for a while but now seems to be back.
Mac is running Catalina 10.15.7
OS is at max for this slightly older Mac.