Some refrigerators can last 10-12 years while others might only last 6 years.
If your refrigerator isn't cooling check the air flow to the bottom part of the refrigerator from the top freezer.
The bottom part gets cold from the air in the freezer through an air duct. Make sure that air duct is clear of ice.
Sometimes those air ducts from the freezer to the bottom part of the refrigerator gets blocked by ice and then the refrigerator won't get cold.