No heat coming from the heater, where is the blend door actuator located?

When the vehicle is at normal operating temperature when you turn the heater on there is no heat that comes out of the heater the fan works and so do the controls for defrost mid floor, just no heat. I have the part it's a Dorman part #604224 blend door actuator. The problem I'm running in to is that I cannot find the part that I have in my hand any were up under the dash I've watched ever video on the internet. I just can't locate where the part is located, it's not behind the glove box.
And it's not on the driver's side above the gas pedal I just can find it please help many thanks. Again, thank you I'm advance.