center right vent blows cold air the others are warmer

I have a 2010 Dodge Avenger RT the center right vent blows cold air the others are warmer. I bought the car on 06-12-2010 and it has 16,581 miles on it now. It takes 20 or more minutes on the interstate to cool the car down during hot weather with whole. No work done. Trying to find some info so I can ask auto dealer to check out. They don't seemed concerned about two different air flows.

Thanks :-)