heater on 2007 Buick Lucerne

No heat on passenger side 2007 Buick lucerne.

Asked by for the 2007 Buick Lucerne
This is typically a passenger side blend door problem and is a labor intensive repair.
I have a lucerne with the same problem but its a manual system and only consists of one door and one temperature actuator. A gm rep said to change the heater core which was weird to me but I cant see the problem being the actuator as it is doing its job if the driver side is getting hot air