Plutonium

Hi everyone. I'm writing this to find out what to do in this case because I'm literally new to this community. The thing is, yesterday I registered everything normally and all, installed Plutonium and the game files on my laptop, and when I tried to start the game, it said it couldn't authenticate, And out of nowhere I get banned for no reason And I want to emphasize, I'm new to this community and I would never use any cheats or hacks because I just wanted to play zombies and I don't know how to mod the game yet. I even created another account thinking it was a mistake, but nothing. If anyone knows a solution, please let me know as soon as possible.