2016 Premier HVAC issue

Newb here 2016 Premier going to give you the short and sweet of it not to bore you but I have a story to tell you of a dealer burn that your head would spin more later

Car in or out of climate blows ONLY COLD AIR DRIVERSIDE UNLESS IN HI! So it's either 90 or 0 temp on driverside passengerside works fine.

Is there a easy way to access the actuators? Anyone removed panels have a play buy play?

TIA