WD Drive content not visible after some time

I am using a new WD My “Passport for Mac” 2 TB, starting under macOS Catalina and now under Big Sur. It is used for TimeMachine backups. Since the beginning it happens about 2 or 3 days after last boot of my iMac that TimeMachine cannot start the backup as the TimeMachine folder was not found. Opening the disk in the Finder I don’t see any folder or file. Opening the disk in the Mac Terminal and listing its content with “ls” it also shows no folders nor files. Only a reboot of the Mac brings back its content.

This is the third disk of that type that shows this phenomenon. A second non-WD disk that I am using for such backups alternately behaves normal.

Why does this happen only on WD drives and what can I do to resolve the issue?

Hello,

Please refer to the following KBA: https://support-en.wd.com/app/answers/detail/a_id/14800/

This KBA does not address my issue. Of course did I test the drive with Apple’s disk utility, it tested it OK. Since this issue happened on three different drives of exactly the same type and since another drive without any problem since more than 2 years used in parallel with the WD drive, it must a unique WD issue.