Online backup - storage issue

I am using online backup for two computers, which I started doing less than a month ago.

 

The online site shows one computer has files backed up of 218.26 MB, the other 163.26 MB (total:  381.52 MB).  These look about right.  Yet I am being told that I have used an alarming 1.10 GB of my allocated 25 GB.  What is going on here, and how do I get the total to reflect reality properly?