Sony CDX-C500R problems

hi all,
i had this cd player and it kept skipping and found out it was a faulty laser so bought another used cdx-c5000r thats been working fine.

only the other day it was working fine one minute, started skipping as it was a scratched disk so put a clean original cd and now it doesnt play any cds what so ever, just the radio works, even when the cd is in and i try and skip a few seconds of the track it just beeps but doesnt scan or skip just nothing happens and it doesnt make a laser loading noise now either

how can it just work one minute and not the next?
whats wrong with it?
help needed asap

cheers