Tailgate noise

Hi everyone, just needed some help on something that’s been driving me mad on my 2016 Q5. When I open or close the automatic tailgate, it makes a noise as soon as it opens and when closing it just before it shuts at the end. The sound is like a rubbing/ whining or catching onto something. I’ve tried this on an incline and flat road, same noise happens. There’s no obvious damage to the struts, panels, rubber bits etc, there is some scratching on the tailgate catch but not sure whether that’s causing it. Would something like this be covered under non Audi warranty? Any advice appreciated!!!! Thanks. 😊