Chronic fatigue syndrome is a rather serious disease (https://ivypanda.com/essays/chronic-fatigue-syndrome-and-thy...). The condition does not improve even after a good rest. This disease is especially characteristic for residents of populated megacities. The main thing to do is to streamline the ratio of work and rest, rational physical activity and, of course, the normalization of the diet. It may be worth talking to your doctor about taking vitamins.