Samsung refrigerator not working

I have had several issues with this model refrigerator. I had a repair man come and fix it soon after we bought it. Soon after it started icing up under the vegetable drawers and the water dispensor stopped working. We defrost and get the ice out repeatedly. Then the ice turned to water and now the freezer stopped cooling and a week later the frig has stopped cooling as well. Could this be a defrost sensor? Or something else.

My refrigerator not start. What i have to do?

REFRIGERATOR STOPPED WORKING SUDDENLY. ALL OTHER ELECTRICITY IN KITCHEN AND HOUSE OK