Digital piano keys malfunctioning

I have a Yamaha p125 , suddenly when I'm playing on it the G and G# keys started misbehaving on all octaves , if I hold down one key it kills the other(it doesn't sound) , if I press them consecutively but release one before the other they work normally, if I press them both together they work normally , only when holding down one and trying to press the other the other doesn't work.