Could you please tell us:
1. Is this a frost free fridge with two doors; one for the freezer compartment and a larger door for the fresh food compartment?
If so, there are a number of reasons for the fridge not to be cooling properly besides it being "shot" (so to speak).
Can you tell us whether you can hear the fridge compressor running at all?
And, when the fridge compressor is running, do you feel a slight breeze in the freezer compartment?
2. Is this a manual defrost fridge with a single door and a separate freezer compartment with it's own door inside the fridge?
If so, can you decribe the way any frost is forming on the top, back and floor of the freezer compartment. Is there frost forming uniformly over the whole surface of the freezer compartment or is there a "snowball" forming where the evaporator line come into the freezer compartment, or anything in between?