Make sure the freezer door is not sagging. Door magnetic gasket must fully mate with the metal frame of freezer. If ok, check under door for torn gasket.
If ok, you can try to re-form the door gasket with a hair dryer, then before bedtime, duck tape the door closed with the gasket pushed in further. Next morning, remove tape, door should now be ok.
If still bad, replace door gasket. You can click on model # above to get part #.