how can I fix my hotpoint rfa06p?

Hi, I have a hotpoint RFA 06p fridge freezer. I left the fridge door open for 8 hours and came back to find the fridge hot. the freezer was also starting to thaw. We have left the appliance unplugged for 48 hrs as recomended and when turned back on the fridge stays warm and the freezer gets cool ish. When back on I can hear a water trickling type noise at the back. The fridge freezer makes a normal running noise and the unit at the back whick I think contains the r600 gas is hot to the touch. Have you any idea of the cause? Thanks Matt