Time Machine won't back up because there are two drives named Macintosh HD
Even though one drive is named Macintosh HD - Data, Time Machine fails to make a back up now that I've moved up to OS 10.15.4 Catalina.
Which drive should it be backing up? How do I get it pointed to that drive, or what can I do about renaming one of them?
iMac 27", macOS 10.14