This could be a couple of different things. First, check the coolant level in the engine. When the engine is cold, remove the radiator cap and make sure it is full. Don't just depend on the reservoir.
If that is full, then suspect the air mixing damper control motor has failed or something has come apart.
If you look below, I attached the directions for inspecting this component. The electric actuator is what moves the air mix door allowing either heat or AC to enter the vehicle. Take a look through the directions and let me know if you are comfortable performing them or if I can help in any way.
See pics below.
Images (Click to enlarge)
Saturday, July 16th, 2022 AT 5:50 PM