Somehow it has lost the cooling gas. Leak will need to be traced, repaired and then refilled with correct gas. Not cheap. Phone around and get quotes. Make sure they take it away and repair it properly and give you a warranty. Some will just come to your house, pump in some gas and take your money. Gas will just leak out again after a while.
Lincoln Appliance NZ
April 2012
Automatic Answer
While you wait for answers, we may have found some information which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix freezers.