"Bad Challenge"

For days now I've been rejected from games and lobbies 4/5 times with the "bad challenge" message before actually being able to get into the game, and once that game ends I've sent back to the main menu with the bad challenge message too. I've verified game files, I've tried countless different servers, I'm at a loss as to why this is happening... It happens for every game mode from BR to mixtape. I'm a steam user in EU for clarity. I can reply with more details if needed but any help would be greatly appreciated.