I dont think you can send PM's yet, so i'll post here.
I'm wondering, when you reached prestige 4 did you keep playing and then it immediately bugged out?
Or did you actually activate the prestige, got prestige lvl5 and then in a new game it bugged out?
I can help out fixing your stats, can you read pm's? Then i'll send you a link with a fix
i'm aslo having this issue where Reach prestige 4 then After that went back to the menu and go into the map it's didnt prompt me the Prestige to next level then when kill a zombie you just level up and your rank is total noob.