Keybinds messed up after one game

I got on my friends account, switch to my keybinds. But after one match, it will revert back to their old keybinds and you cannot change in-game. Same thing goes the other way. My friends plays on my account, switch to his keybinds, SWITCH back to my keybinds when he's done with my account. I played one match and after that it will revert back to HIS keybinds and you cannot change in-game