We have a similar problem with an old fridge we use for extra storage: frost forms inside the door. You have a lid, so I'm guessing you have a chest type freezer.
The remedy is to melt the ice in the lid, which can be a slow, damp, messy job. Unplug the freezer, open the lid and keep it open. Cover the food with newpaper, and an old blanket or two to help keep the food frozen.
Use a hairdrier, heater, or hot air gun plugged into a ground-fault protected outlet to warm the inside of the lid. Be careful you don't get the lid too hot! After it is warm to the touch all over, check to be sure the water is draining. If so, feel the lid for cold spots, and rewarm them as needed. This may take an hour or two.
When done, REMEMBER TO PLUG IN THE FREEZER.
Tom Gloger, November 2007
