Some keys don't work on the Yamaha P-150

Just bought a P-150 today but 7 keys don't work.

It's in the higher range and it's the E's and the A#'s.
I opened it, disassembled and cleaned it.
Found this lifehack on youtube about colouring the print with pencil.
Found the suggestion in this forum about turning it upside down and tapping it.
Nothing worked so I am running out of options.
Do you have any idea's what could be my next move?
Maybe the print is broken? How can I check?

Not sure if it's still worth to repair it, maybe I am better of buying a newer one.

Any help would be appreciated.

Kind regards,

Feddo