Command and Conquer 3 Tiberium Wars, Online Account not found

[sapphirebolt]

Everytime I try to play multiplayer online I get an issue with logging in and I know my username, password, and online ID is correct. There is no problem with my game because I can log into my friends account on my game(we checked). I dont know if I used the right email for my cd key and I need help, what problem do I have and can it be fixed?