Time Machine Stopped Working Overnight

Time Machine stopped working suddenly. The error was that the disk didn't have write permissions. I spent four hours debugging the issue, including about 1 hour with the Apple Support team (who were completely useless).

The only solution I could find was to reformat the disk and start the Time Machine from scratch. I have been having this problem since I upgraded to Catalina.

Anyone else facing similar issue. This is the second time it's happening, want to be prepared for the next time.