The blend air door actuator is for temperature control. In this case, it sounds like you have an airflow direction problem. That is controlled by what is called a mode door actuator.
I attached a pic below showing the actuator I'm referring to. What I suggest is this. Remove the two bolts holding it to the HVAC box. With the wiring still connected, see if it responds when you select the vents.
Let me know what you find or if you have other questions. Note: The actuator is on the right side of the HVAC box under the passenger side of the dash.
See pic below.
Thursday, January 13th, 2022 AT 9:02 PM