Flipkart — Unprofessional service in returning or refunding for a faulty product

I received this product on 3rd Dec'21. Since day 1 the mobile charging is draining drastically without using much applications because I have not installed higher number applications and specifically no gaming application but still charging is getting drained so fast and raised this complaint with Flipkart and they asked me to contact Apple which I have contacted them. The first person remoted into my phone and changed few setting and he even noticed that over the remote call the battery is drained drastically hence he asked me to do a factory reset and monitor for 24 - 48hrs but after which still the issue remains same. Again I contacted apple support where the second guy remoted into my phone and he observed the same where the battery is getting drained hence he checked with second level support team and they said could be hardware issue. Hence I reached out to Flipkart reporting the same and their response is very unprofessional and pathetic because they promised me that if apple not providing enough support then report to us where we can help in arranging the needful but all were fake promise they made to me. I have been a legitimate customer to Flipkart but they fraud me in handling this case. It's so depressing and annoying because I paid a huge amount for this product and the behaviour of Flipkart is so bad and pathetic. I cannot even use this phone because I'm panicked & scared if I use then the battery might get drained and it will go to switch off mode which is of no use after spending this much money on the product. Hence I need a justice because of this fraudulent activity and I want them to pay back my amount.