I agree with Mark; the missing version number in that log message seems unusual. I suggest investigating further.
Do you have any other backup processes running concurrently on this cluster or another one?
It seems Rclone is unable to write to the backup destination: are you sure the destination credentials have enough rights? Is it the iDrive S3 destination, NS8 backup failing on IDrive e2 S3 - #4 by davidep?