ok compressor running ,fan in freezer running ,sounds as if either the compressor is no longer pumping refrigerant.
Or it has a leak in the sealed refrigerant system .
and for this old of a unit .
the compressor is $280.00 dollars if you where to purchase it .if a servicer does the ordering and replacement of the compressor about 600-800
And a sealed system repair for the leak and the compressor would be $300-$400
I don't know how much you want to spend on a unit this age.