Problem backing up to external hard drive.
When I try backing up to external hard drive, I get a message Backup Drive Not Available; try backing up again when My Passport is available. This happens when I have the My Passport disc inserted. Also another message indicates to be sure backup disc is connected or select a different backup disc. I only have the one My Passport disc. I don't know what to do and would appreciate any suggestion.
MacBook Air, macOS 13.4