frostfree freezers often stop working when the internal air ducts get choked with frost and ice. Remedy is to unplug, empty, eat all the food, open the doors and leave open for at least 24 hours, or after no more water drips into the cabinet or into the collection dish at the back (pull the machine away from the wall and keep emptying the dish, as it is liable to overflow)
if it works... nil cost fix
if not... nil cost and you're back where you were anyway.
Do not turn it back on until all the ice has melted and run out - it is in ducts and channels concealed in the back lining.
obviously the fault might be something different, but with frostfrees this is quite common. I threw one away before I discovered how easy it is to fix. Excess ice can arise if the door is left open or steaming foods put inside, or if the door seal is worn, cracked or loose.