LS Focus XR5T Brake light issue

[mandi]

Hi Everyone

I'm having issues with my focus xr5 whenever I put my foot on the brake pedal the brake lights don't work but my dash lights come on and my brake lights are my parker lights.
When I have my parker/headlights on the rear lights are all on or not at all.

I have changed the rear globes, but I'm still having the same problem.

Would anyone have an idea what is the problem?

TIA

Mandi