My nintendo gamshark menu doesn't come up

Goodafternoon i have a nintendo gameshark for the gameboy andvance SP, i have looked fairly everywhere for how to fix it and where to fix it, nothing seems to tell me how, i cleaned it opened it and im using the right gamr (pokemon fire red) and i have tried different games multiple times.... MANY MANY times, i was wondering if there is anyway you know who can fix it or where i can or how please...

Thanks in advance my email is

juanocampo21@yahoo.com