License plate light problem
 

Recently, I received an inverted bulb warning on my R56. I checked all the outdoor lights and the only problem I saw was the license plate lights. I bought several bulbs to replace them but no success. I checked all the fuses, everything seems ok. The trunk opener is working fine.
https://cimg1.ibsrv.net/gimg/minicoo...485342c0c.jpeg
I decided to buy a whole kit- the trunk garnish molding trim with wire...the lights are still not working. Any input what seems to be the problem?