Have a stuck key, somewhere on the board ? - PC ? Try another KB.
Onscreen keyboard means he's probably on a tablet PC with a touch screen. Will make it harder to swap it out.
Since the keys you are having issues with are right next to each other, could have something in the keyboard that is sticking the keys together, usually soda, jelly, etc.. will do that. Or just move the keys around a bit in that area see what happens.