Rear lights on the left do not go pears ok

Hi guys, I'm getting into my A8 4.2 Quattro year of construction 2000 and the on-board computer is showing me a broken bulb. I got off because I've got some. Look back left no one goes right yes and the blinker left and brake light goes also???????? Did the bulb change but no of both on the left side goes I checked everything but find nothing can help me???????? Greeting Artur