I've got a Fisher and

Question

I've got a Fisher and Paykel fridge freezer (fridge on top.The freezer appears to be fine (although have had problems with build up of ice in the past). However the fridge is too warm- it takes it being closed overnight to get down to the right temperature. I've thoroughly defrosted the freezer. I think it is the fridge fan that isn't circulating the air properly. Does this sound right or any other ideas? I've checked both the fans and they are intact and moving freely and I've checked all obvious connections so I'm running out of ideas- help!