The stove has gone darker in aptches... is there anything I can do? Please please please help

Caustic will eat away the aluminum forming sodium aluminate. Naval Jelly makes an aluminum brightener that can be used. Wear gloves and brush it on and the use 0000 steel wool to polish out the black areas. Naval Jelly contains phosphoric acid that is used to clean airplanes bodies. Do not use muriatic acid because it is too strong and will eat the aluminum away too fast. You probably won't be able to return it to the original look.