Hi, it could be due to Gastritis.
Avoid tight-fitting clothing. Clothes that fit tightly around your waist put pressure on your abdomen and the lower esophageal sphincter.
Avoid foods and drinks that trigger Gastritis. Everyone has specific triggers. Common triggers such as fatty or fried foods, tomato sauce, alcohol, chocolate, mint, garlic, onion, and caffeine may make worse. Avoid foods you know will trigger your Stomach pain.
Eat smaller meals. Avoid overeating by eating smaller meals.
Don't lie down after a meal. Wait at least three hours after eating before lying down or going to bed.