Apple India — I reported for (battery draining issue) not yet resolved

I had reported for battery draining issue to imagine apple care - gopalan signature mall bengaluru. They found some part failure and replaced but battery draining issue persists. Contacted apple support they are big cheaters trying to escape, no follow ups no proper resolution. Simply they deny saying working on it will get back to u.. Called them and spoke to them more than 60 times. I asked for replacement though it is a 10 days old mobile. They are denying unless they find an hardware issue. I questioned them already display replaced without seeking my permission. For that they said it is procedure and now battery draining am complaining them they are very careless and those people are very lethargy and all the cheaters are escaping instead of getting resolved. Lost faith please help me!!!