How can I fix my Hotpoint FFA97 fridge freezer?

My freezer is working just fine, but the fridge is no longer cold. It was making an odd noise at the weekend, and now the digital display indicates that it is trying to get to temperature and there is the sound of a motor each time the door is closed, but still no cold air coming through. I have now completely emptied it and left it overnight to ensure it was not a case of something blocking airways etc but no joy this morning. Help!!