@Mr-Android I just tried this and it seems to have worked for me.
My routine:
Manually prestige (statsetbyname plevel {value} ) to get 10 classes.
Got a few permanent unlocks. (Perks are locked for prestige 15)
Then did the command for prestige 15.
Went onto one of my servers and I have no problems whatsoever.
I don't know if it's because of pure luck, but I do want to thank HannesC for the command.