My defroster is blowing out hot air but not defrosting my window

That's done on purpose to blow dried air at the windshield to help it defrost faster. When in defrost mode, the AC is running. Standard feature on most cars and trucks

Your windshield and rear window has defrost outlets that exhaust right onto your front and rear window glass. Your side glass probably doesn't enjoy this luxury.

front or rear defrost?
what windows, there are many, front windshield?????
front:
dont use RECIRC mode. use fresh air, only
and make sure the dampers are in fact sending hot air to the windshield. if the dampers are not working it needs service
or a simpled blown fuses in the fuse box.
also, the car can have water engress. are the any damp spots
on the carperts. anywhere.?
are you using the A/C defrost mode, does it work.
do you know how to tell, its easy, check A/C mode.
A/c is also a dehydration system for the whole cab, it even ejects
water to the ground as you drive.

Sounds like defrost door on heater box is not work You need to get under dash and check controls on the box. Good luck

check for anything that may have fallen into defrost vent poss jammed air blend doors.

Yes, that's the way it works.

the deflector flap that move to direct air flow is stuck under the dash.

The Heater Control Valve has failed. It defaults to full defrost mode when it fails and blows hot air even when the A/C runs. Replacement part is $105 ...google Autohaus AZ for online parts ordering. BTW...HCV is located in the engine compartment right in front of the driver position in the corner by the firewall and inner fender...you'll see small coolant hose running to it.

common problem, check under dash by the gas pedal if control arms are muving went selecting from ac to heat cuz this it is the control for the vents to go from ac to heat and to defrost.

You may need to replace the mode selector switch.