Windshield partially freezing up
We have a new 2019 Thor ACE 30.3. During a recent trip on a cold, rainy/sleety day that caught us by surprise, but we had to get home. Problem, the driver's side windshield, about the left two feet froze up and my left pantleg became very cold. There are 4 defrost vents but looking today only 2 have hoses connected and no air comes out of the outer two vents. There are no other hoses or connection points under the dash. Any thoughts?