Kingdom hearts navi-gummi problem?

So I am at level 20 and i have cleared and found the keyhole to the planets: Traverse Town, Wonderland, and Tarzans place. I have defeated all the bosses in those places and i need to move on to the next planet. But Cid keeps telling me that I need another navi-g piece. Is this a glitch or something? Because i know that you get a gummi after you defeat the trickmaster and after you have defeated Claton. Im totally clueless. Help PLZ?