Can't pick new character to obtain

So let me get straight to the point so i have the choice to pick illaoi, riven, or garen but it won't let me click on select for any of the characters it worked just fine with tristana. caitlyn, and ezrael but now it's just bugged so i can't play league because of this dumb bug can someone please tell me how to fix or at least how to get rid of the bug.