xp bug

So about a month and a half has gone by since my character Lucifer achieved level 260 in-game, with the cap at 270. However I am not able to gain any exp, since I don't know if this is a bug or not. What the problem is I do know that the xp bar at the bottom won't move no matter how much exp I get. The exp bar constantly flickers red and white and I manage to level up in around 2 months at high tier, but the game says that level 270 is the cap. I tried reporting it as a bug and I didn't hear a response for 3 weeks (albeit was over Christmas) If anyone could clear up my confusion or if you have the same issue at level 260, please let me know.

thanks