My Audi's cabin lights won't turn on when I open my door?

The overhead lights are working perfectly good. When I 1st bought it, the lights could automatically fade on. What could the problem be?

they are either switched off manually on the dash or overhead, or else the wiring/fuse is messed up.

First thing is check the fuse those lights are intended to last for a long time, If the fuse isn't blown then check the bulb and be sure it blown hope this helps,