Why do I have no air blowing thru dash vents when AC is running. on 1997 Oldsmobile Bravada

I have air blowing out at the vent by the gas pedal and out of the window defroster vent on dash top. But none at all across the front dash vents. AC and heater seem to work fine, just no air blowing from dash vents that usually blow directly on driver or passenger.

Asked by for the 1997 Oldsmobile Bravada
Sounds like a mode control actuator is defective. The mode control directs the air out the vents, out the defrost, to the floor etc. Sounds like this aspect of your heater A/C has an issue.
Is this part of the heater/AC? And,is this a job that requires removing dash?