Volkswagen Touran climate control - no heat

My car is two years old with 9700 miles and after visiting my local dealership as I had to have the temperature set at 22-26 C to get any heat. The dealership said problem was it need ed a software upodate! After collecting the car it satrted emmitting heat on the way home at 22C in the face vent setting but when I change it to foot well or foot well/screen it went back to cold. The only way to obtain any heat is to set the stat between 22-26C.