2 part AC problem

[meyerbj81]

I am having two problems with my AC control in a 2011 6.7 king ranch. Both problems I assume are due to blend doors however I am seeking further advice. When the truck is first started it will come out on heat on the passenger side. Sometimes after 2 minutes, sometime 20 it will eventually blow cool after switching the setting multiple times. Second problem is that it will not switch to defrost, only dash vents and floor vents. I have seen multiple articles on replacing these on a 6.4 but none on a 6.7. Any guidance would be appreciated.