Heat wont turn off

I'm trying to determine if your AC is functioning, or if you have a problem within the dash ventilation system directing proper air flow. The air conditioner may not be functioning mechanically. There could be a low charge caused by a leak, or a faulty electrical component. Do you hear the AC compressor turn off and on when you have the AC on turned to cold? You typically will hear a clicking noise. There's also some pipes towards the back of the passenger side that should get cold with the AC running. They run from the AC compressor to the accumulator and into the evaporator, which is what gets cold inside the car and produces your cold air. If the pipes are not cold, and the AC compressor is not "cycling" (click on, click off...) as normal, then you need to have that system checked. If you do have cold temperatures on those lines, then you could have a temperature blend door issue in the dash.