Why is my freezer hot and cold

Why is my freezer hot and cold I defrosted my fridge freezer (indesit) yesterday cleaned inside and out. Even the back where the elements are as this is the only place you can get into all other parts are sealed. Once I defrosted it i switched it back on and sincethen myfridge freezer is freezing up then it's defrosting. My food is starting to defrost. Help anyone?