The operation was not successful message

[lnjr]

I have only been using this software for about 56 weeks now and I went to create a backup like I have doing and this time I got a message saying that the operation was not successful.   There was no other information with it.   I checked the external hard drive that I am saving the backup to and the folder was completely empty.  There is plenty of room on that external hard drive so I know that is not the issue.    
Why did I get this message and how do I go about resolving the issue so that I can continue to use this software to back up my windows 11 Pro computer.?
Thank You