Air Amplifier. Vents not working properly

Ok Folk, I did some research on the forum and came up with air amplifier, thank you for the info.
2012 Prius C 3

my issue: everything works with the a/c.
The only issue I’m having recently, I can’t get the air to come out of the vents on the windshield, when I select defrost/windshield or windshield/feet the air comes from the front vents, winters in NY make it impossible for me to not have defrost. I was able to get to the air amplifier because of the pictures on the forum... I can buy a used amplifier but should I suspect something else??
Aren’t there actuators that move the vents ?
Any help would be greatly appreciated
Thanks