I searched the replay vault, and a player with your name (the name that shows up on your forum posts, specifically: "thenewIKB") created some games on November 14-15, 2020. You would not have been able to do that in November of 2020 unless this account was already linked to steam.
Are you trying to log in to the FAF client with the username "thenewIKB"? Try logging in to FAF with the same username/password that you used to log in to the forums.