when I turn the heat and air off it still keeps blowing cold air in the floor..

You may want to confirm the ventilation system settings; you could be allowing ventilated air in even when the system is off. Refer to your owners guide for this information on proper settings for the heating, ventilation and air conditioning system (HVAC). Alternatively, if there is some kind of malfunction occurring, only troubleshooting the system will reveal the cause of concern.