Endoscopy may or may not be done. But main point is that Gastritis reccurrance is very common and easy. So u can avoid endoscopy for now. Protocol says endoscopy Should be done that's why your doctor has told you, but you have right to avoid it on your own responsibility.
Next Steps
avoid spicy foods coffee tea cold drinks alcohol smoking junk food etc.
Health Tips
but even if u are improving do not stop the Treatment.