Casio music keyboard. Spares or repairs (Southdown AL5)

This is a 5 octave, 248 tone electric keyboard. Was working perfectly until recently, but unfortunately now has issues. When turned on, it powers up, but mostly displays an error display and no sound comes out. If the on/off button is pressed multiple times it will eventually boot up OK and is playable ( just managed to get it working, once only, see photo) May be mendable, I really don't know. Any questions welcome. Comes with instructions manual, power adaptor and batteries.