Sears Kenmore 16 series fridge. My fridge is not cooling enough in the big section, but freezer

Question

My fridge is not cooling enough in the big section, but freezer runs just fine. There is 50 F in big section of the fridge. Freezer feels just fine. i will say that the fridge is old. Guessing about 10 years, maybe more. Its a Kenmore 16 series It was here when I bought the house. Any help would be appriciated. Thanks guys.