brake lights and shift lock

[yosef7]

1992 Volvo 240
I have been having trouble recently with the shift lock not working. I must manually undo the lock everytime. I have also just lost brake lights. as well as backup lights. I am told backup (rev) lights are associated with the shift lock mechanism. But why no brake lights now. I have checked fuses and light bulbs. All work and are fine.

Some ideas and solutions please. Cannot drive for fear of being pulled over.