The freezer and fridge are not cooling nor freezing

The freezer and fridge are not cooling nor freezing My fridge is a Samsung that has double doors and one door at the bottom for the freezer. Both the freezer and fridge are not cooling nor freezing. The temperature reading is 23 and 24 degree Celsius. Someone working with them said it's leaking. What is leaking. And could be the problem. How can I make it work ..DIY.