Check the power outlet by testing another appliance in it. If it does not work, use another circuit.
Turn the temperature control to a colder setting. It will take several hours for the temperature to stabilize after adjusting.
Open the door less frequently. Warm air enters the freezer every time the door is opened.
Check the seal of the freezer door for obstructions. Packaging or objects blocking the door seal from closing will prevent the freezer from maintaining a sufficiently cold temperature.
Allow the freezer four hours to cool down if it has recently been disconnected from a power source.
Listen for the compressor to turn on. If the compressor never turns on and the freezer is receiving power, the compressor may need to be replaced. Contact a qualified technician for assistance.