Time Machine won't back up due to Macintosh HD - Data
I keep receiving the following alert "Time Machine could not back up the disk “Macintosh HD - Data” because a snapshot of the disk could not be created."
When I have looked into it, I think it's because the HD - Data drive has been used to install the BigSur update. Is there a way to reinstall the software and then I can use Time Machine again to continue my backups to an external drive?
My "My Book" is 6TB and the HD -Data is taking up 980.12GB.
iMac 21.5″, macOS 11.5