Account banned after match ended

I played a match against a relatively strong player and won, but when the match ended I received a message with a lower content Sorry, your account was banned for a few hours, and now it's been more than four days. I don't know what I did wrong. I was playing as a guest account and didn't realize I was required to link an account to the game to protect myself from being banned. I don't know how long it will take to get the ban lifted, or if it's a permanent ban.