Samsung RS21DCNS Fridge Freezer?

I have had the above fridge for 2 years, kept the freezer running at -23, the fridge at 1, perfect for chilling, not had a problem untill the other day, digital control still says same temps, but the fridge is not as cold, for example, lurpack butter straight from fridge spreads like its been left in the sun for a day. Freezer still working, as is the water dispenser and ice cube maker. On opening fridge door this morning water dribbled onto the floor but could not find its origin. Anyone know my problem?