I've never had this issue myself before, but I did come across another plot with your name on it that belongs to someone else. This is at plot # -23;5, and the owner (on the sign) appears to be Qu3B. If you do /plot list mine, what output do you get?
Edit: I've noticed that one of the players seems to be a Meep newcomer, while the other seems to have logged in only recently after a long hiatus. Admins + Techs: is it possible that database corruption has led to mis-mapping players who are only recently claiming new plots in Creative?
Double Edit: I've also noticed there there appears to be an instance of a plot in Creative where the large splash notice says "Owned by Acceleradiance" but the border of the plot shows that it is unclaimed (and there is no owner sign on the border). They seem to have changed their name just recently as well. This is plot # -26;13.
