2001 sprinter 311 back light not working, please help

[Wolley jumper]

Hi, I have a 2001 311 sprinter. My MOT has failed on my rear passenger side back tail light. When I try to turn this light on the passenger side light doesn't work. I've tried checking the fuses and ive replaced the bulbs, still no luck.
I've also noticed that the interior buzzer for the lights no longer works in the cab and all the orange reflective lights on the exterior bottom of the van no longer works. Any help or guidance would be much appreciated

 

[DREAMER NO2]

Take a look at this ,,,come back if it is not the problem