Heat issue

[goodgigi]

2016 RR HSE- Driver side heat vents just blow cold air. Coolant system/water pump has been done. Passenger side heat ok, but rear heat seems to be the best. i’ve heard the term actuators and maybe they’re not working.? I tried changing the climate controls, but that doesn’t seem to help and sometimes the climate controls, when I go back in there, have changed to something else when I didn’t change them… how can you not get warm heat into a vehicle that’s running hot??? ugh!