What could be the reason for the white part of your eye looking yellow?

Jaundice. This is the buildup of bile pigments which is the result of liver or gall bladder disease. Incomplete excretion of these pigments stains the sclera yellow. With resolution of the problem, the white of the eye will return to normal. Good idea to see your gastroenterologist or primary care doctor soon!
Eye yellowing. This can be normal or due to dehydration, liver disease, certain growths such as pingueculae, any cause of eye irritation, or other issues. See an eye doctor.