@shngo yes, you have pirated files, those are not supported. Get your game files from steam and then point plutonium to your steam game files and you'll be good!
Enter the new email in the change email page (while logged into the account of interest) and it should send the confirmation request to it: https://forum.plutonium.pw/me/edit/email
I had sync every frame on and it happened a lot. Turned it to no and unlimited frames and it still happened but less. Locked the frames at 200 or less and it happens less often but still sometimes. It's the connection interrupted error. Not sure how to fix it. My internet works fine on everything else. System is a brand new PC. i9/5080
Sadly, they don't do unbans. You accepted their anti-cheat policy when you created the account. If you have read it, it states that any tools used is banable, they even showed you how to disable and go into lan mode so they the tools work but you lose access to the servers.