Heater suddenly stops working air conditioner currently still works

At first, my car stopped switching from defrost to facial to foot when the heater or air was on. This went on for months it wouldn’t switch from defrost to put. It only blew out through the vents going towards your face heat and air. Both worked just fine. It just didn’t blow out of anything other than the metal blowers. All of a sudden two weeks ago, the heat just stopped blowing hot. It just blows cool. The AC still comes on and still blows just fine. It doesn’t switch still from defrost or otherwise just towards the face. It’s winter time or getting ready to be winter time and I need my heat to work. I’ve checked to see if the radiator hoses are hot and cool like they should be. They seem to be fine. I’m not sure what fuses to check first or where to go on this one, any advice would be helpful thank you.