I'm level 40. Whenever I do anything that says that I gain xp there is zero change from "255,072 / MAX" in my bar. But I see opponents coming up in the battle listed as being level 41 and higher. What's going on here?

... Oh, weird. I just searched in the tower listing for a name that the battle showed me as a level 43 player and they're actually only level 7. And searching the other two names (showing as levels 41 and 42) that I see right now, both come up with zero results on the tower.