they made a new update that made it so you can level up of "non white listed" maps and there have been glitch ever since but not too many were effected. things such as not being able the level your character or perks go back to 0 durring rounds. its crazy but there a new game and even though i disprove of there recent action such making leveling maps useless i still this its a great game.
If you're playing solo mode, there's a bug introduced in the latest update that halts leveling up in Solo.
I heard what works is creating a listen server (from the main menu) and then starting the game, and then quitting back to the main menu. Entering the server sets the perk rank to enabled, and then you can start tanking up in solo.
Once you quit the game, it'll reset, so you'll have to do that every time you want to rank up in solo mode.
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