Is this going to be a big problem

Noticed it about 2 weeks ago when I was driving it is on the rear window on the passenger side. I am going to take it to the dealer next week because it should be covered under warranty. Are there any suggestions to fix this or will the dealer have to take off the whole headline to take it off. I am not sure how this even happened the truck is just a little over a year old.

 

I would fix it myself before taking it to any dealer around me. Some kind of headliner adhesive should work, or just pop it back in. Lord knows what they would screw up given the opportunity.

 

That's what I have been doing just popping it back but comes out after driving around.