As I understand it, your grandfather is now in Florida and you are in Alabama. His original POA is from an Alabama attorney and your Florida uncle has somehow convinced your grandfather to change his POA to drop you and add him as Agent. Is that correct? If so, you will need to enlist the help of a Florida attorney near where your grandfather is now living in order to challenge the capacity issue of your grandfather. Please reply with a city and zip and we can find you a local attorney who can help.