Yamaha Motif Xf7 Ab and D keys no sound

I encountered a problem yesterday with my Motif XF7 the Ab and D Keys from the lower register to the first D key after middle C does not work/ no sound. I tried cleaning the contact boards under the keys to no avail. Also there are two 23 pin connectors connecting the three boards under the keybed I don’t know if they are the problem I tried cleaning them as well however the problem still persist.
Also can you tell me where I purchase the 40 pin connector and the two 23 pin connectors under the keybed?
Please help or provide suggestions

Regards
Glenville