I agree with Bill on this. If you have the INSIDE of your windows fogging up, you have moisture inside somewhere. You may have a sunroof drain plugged, torn or missing door vapor barrier, leaking windshield, or leaking heater core. You may not feel the carpet wet due to the foam padding soaking up the moisture, but it’s in there somewhere. Check your trunk too. Moisture vapor can enter the cabin from the trunk. The car needs to be aired out to let the moisture evaporate.