Heat works on one side - blend door actucator?

My car seems to only be blowing out air through the floor vents. It recognizes temperature change and level of air flow but isn't recognizing face, defrost or combo air control. It strictly just stays on the floor vent.

I have a 2000 Dodge Stratus and have been having problems with my vents working. The defroster on the windshield works perfectly fine and blows air, but when I move the controls to switch to the dashboard vents or the floor vents, it won't change. It is always blowing air out of the windshield vents no matter what setting I turn it to. The temperature switch works. This is a problem in both the summer and winter because in the summer when I turn the A/C on, it fogs up my windshield, and in the winter time, my feet freeze. I was wondering if it could be a problem with the switch, or a sensor. I hope it is something fixable.

The a/c works fine about 5-10 minutes, blowing out from the front and or floor vents on the dash panel, with either of the 3 a/c settings. But will then stop blowing out from whichever of these 3 settings are currently chosen and blow out from the windshield defroster vents only, still blowing coldened air. Try switching the vent selector to defroster then back to either of the 3 a/c settings does nothing. Will eventually go back from blowing out of the defroster vents to the a/c vent, after anywhere from 5 - 30 minutes, then repeat this cycle. It never stays blowing out either of the 3 a/c vents for more than about 10 minutes. Any suggestions? Or further t/s? Thanks. Tom

Thank you very much ! !