Indesit c239NF Blowing out warm air?

I have an Indesit c239NF fridge freezer. The freezer section was getting slightly iced up, and then all the food in the freezer became defrosted. I turned off the freezer and defrosted to clear out the ice, but on turning it back on, it is just blowing out warm air from the freezer and the fridge is not cold anymore. Any thoughts on what the problem is likely to be?

Also, is it normal for a frost free freezer to get iced up?