Samsung - Faulty phone received

I bought a Samsung S**FE on **th March, since then my phone has gone twice to Samsung service center, *st time returned saying "software update done, all ok" and second time my phone still with them since **th April (almost a month)
My complaint: Severe heating issues and below par battery performance.
Samsung service center rep himself admitted that the phone is indeed hot, I even joked that I can roast a chapati on my phone. All this is recorded in their camera. But their service rep refuses to accept the issue and have refused to gimme an exchange or refund and also have my phone with them. Inspite of me telling to maintain a single mail trail, yet she sends me a new mail not documenting half the things we speak. No help from her at all. I have no phone for * months now
I did a lot of R&D thereafter and discovered that mine is not the first compliant on S**FE and it indeed has heating issues due to sub par processor.