Hello, my name is Rusty. You may need to have it serviced, the first thing to check is to see if it is in working order. Since it has sat for so long, you'll need to plug it in and leave it sit for about an hour. Turn it on, and let it sit for another hour. This will warm up your electronics gently, as to not shock the system. This will also charge the internal battery. After pianos sit for a long time, the battery can die and it will lose programming. That's what we're looking for here.
Now try playing it, and use the various functions. Does everything appear to work properly?