Ac air does not come out on the dash boared vent but blows on windshield. what is the problem?

How long have you been driving or owned a car? Your A/C is set on front "defrost" instead of main. Turn off the defroster for the front and select the switch to read "main" or if your A/C panel uses icons to display, press the one where it looks like the airflow is blowing air (represented by arrows) towards you and not the windshield. The arrows on your buttons or electronic display refer to which way the air is flowing. Choose the one you want where the arrows show the airflow is blowing out towards you and/or turn off your defroster. (If you have a knob to select airflow, turn it so it is no longer on "defrost" and it points to the main airflow blowing outward).

Defrost has been stronger on all types. Just the way plenums are made. Clear that wind shield first. As long as you have plenty of heat to keep the cabin area warm to hot, it's OK. I wouldn't woory about it.

Possible bad blend door actuator .some gm cars can be relearned to the new climate control head

Check the fan/fans to see if they are working and the fuses. These are the usual causes of a bad vent

Possible blend air door malfunction.

Usually this is a problem with the blend doors under the dash. You either have a vac leak, a dead motor, or a faulty door.
The control opens and closes the doors to direct air thru the heater core and evaporator core along with directing air thru the vents.
When a problem occurs, the default position is the defrost vents to make sure the windshield remains clear.
You can do an internet search for "repair durango blend door" for more info.

My ac is only blowing on the defrost but none on the center dash vents. How do I clean the ac hoses? It may be blocked.

you should know this is easy problem , open up the control AC/blower device and melt with soldering all points over the circuit it's easy don't be scary

it will still blow air on your windshield but the reason the ac comes on is to blow dry air on your wind shield, potentially a cold windshield and damp air could make problems worse. but ive been in the situation before it still works with no noticable difference most of the time

you have a bad control unit, the thing you use to switch from one thing to the other, it needs to be replaced.