Karoq MY2020 Rear LED Light problem

Hello fellows and ladies,

I would like to ask You for a help with my recent problem with my Karoq 1.5 MY2020
Day by day, the right rear LED suddenly stopped working (it dimmed, it is not fully 100% light?) Has anyone experienced a similar issue? Is it something I can fix myself? Is there a way that led bar can be replaced, or does the entire rear light part need to be replaced?
I already checked the Fusebox - all good there.
I cleaned all connectors with contact cleaner and scrap them a bit to made better connection for ground.
I also read on diffrent forum that someone had similiar issue and some kind of PCB module had "cold solder joints" but I couldnt reach that person that he would explain what and where exatcly.
So this is by far everthing that I had in mind to check,

Any more clues and information I would be grateful
Thanks in advance