Climate control problems

Hello,
I wonder if anyone has this issue.
I have recently started using the heating in the Evoque.
During, summer, I hardly used the air conditioning, as I am the 'window open' type.

As I put the temperature to 23 degrees, there is sound of the mechanism working, but there is no or a little trickle of air coming from the central or the side vents.
There is slow heat in the car, but presumably from the leg vents.
As I put the heating to maximum, there is little air from the side vents and central vents.

As I persume, the central vents take in pollen filtered air from the outside, and is not connected to the climate control mechanism.

The garage I use,changed the temperature sensor in the car, but noticed no difference from the original problem.
The car is going back to have it tested. The temperature inside the car recorded 23 degrees, but I told the garage that the temperature recorded was from the leg vents presumably working ok.

Is there a blockage on the air vents or the air conditioning unit has got problems, since I haven't used it much? Any suggestions? Thanks

Does anyone know where the sensors for the outside temperature are placed?