Stomach burning, a very common symptom where a person usually needs to take medication such as pantoprazole or omeoprazole.
I would say that this is an early situation that is easy to avoid. Just reduce your intake of acidic, salty and spicy foods. Such as refined sugar, vinegar, fried foods, ginger, among others. Doing pranayama (breaths) like shitakari or shitali, which cool the body and also aid in digestion.
When it is a more serious situation then we add natural medication which usually has no side effects. It is preferable with fast and good results.