Hi Chomba-121,
Ensure that the date & time is set correctly on your PC.
You can try purging the WD definition cache, in case some corruption exists there.
At a command prompt (admin) enter the following command.
%programfiles%\windows defender\MpCmdRun.exe -removedefinitions -all < enter >
You can also request definition updates from within command prompt.
%programfiles%\windows defender\MpCmdRun.exe -signatureupdate -http < enter >
exit <enter > To leave cmd prompt.
If corrupted data should exist in your cache, this should give you some relief.
Regards, Glen