Hello and welcome. Quite clearly you have some underlying gastrointestinal tract (GIT) abnormality, some underlying condition does exist and in my opinion the endoscopy should have found the diagnosis. I suspect conditions like gastritis, hyperacidity, gastroesophageal reflux disease, acid reflux, etc. You will have to wait for your doctors diagnosis and treatment advise, but for now I would recommend: +Drinking plenty of water +Avoid smoking +Avoid alcohol +Avoid stress +Use medications to reduce acid production like omeprazole, lansoprazole, pantoprazole, etc. Best wishes.