Game shark problems

Yea my console plays games fine but when i try to load my gameshark it says reading disc for a few minutes and then it says there is no disc. When i finally do get it to read it, it says please load format disc. What is this format disc and what can i do to get it to load the game shark??? Okay my problem is that everytime i put my gba sp games in my ds or sp, they will read my game perfectly. But when i put in the gameshark, nothing even happens it says that i don't even have a game in??? Please Help
From:
Mystery Man