Blocking empty notification

Summary

Error notification

Content

We have run into issues with the standard BI notification for new assignments in Learn sending when it is blank. It appears one of our employees have been assigned a course and I think they completed it before the notification run and they were sent a blank notification (attached). All I can think of the reason of them being sent this is due to completing before the run schedule, but I could be wrong. It seems this notification has gone out on other occasions also.

Is there anyway to stop this notification if there is no information in it?