air-conditioner is stuck in the defroster mode and will not change back

Really need to have the Climate Control System diagnosed. Most likely there is a defective door actuator that is not allowing the cold air to be directed out of the vents, when the system only goes out the defrost, that is a fail safe mode for the system. here are some shops: https://repairpal.com/mercury-repair-in-collierville-tennessee