In looking at the team listing, there are:
Possible the server attendant may have misread the stats, and credited your work to someone unknown or a 'phantom'. Best to check with Stanford. But check the config.cfg. file in each F@H folder to ensure you are the one to be credited. An OS crash could cause corruption of those files. (Don't ask how I know.. lost several WUs that were about done, due to power outages.. had to start over!)
F@H.. to solve mankind's maladies.. in our lifetimes!