Nokia India — nokia 6.1 refuse to issue refund product returned

I have shop for nokia 6.1 via nokia online mobile shop. On 6th april 2018. As they delivered me the defective handset/used handset. So i can call 11-12th april 2018 for replacement so they agree but they can continue making me fools in number of mails that for return pickup but not their relevant depptt take any responsibility of all that just makin me fools that wait 24-48 hr. As this now after a one month item was picked up on 8-9th may 2018.
So now they agree with replacement but i have already left that place. But now after number of frustration and inconvenience from their team in replacement i did not longer want any type replacement from them. As i want refund my money back to me.
Pls help me to refund my money back now they making fool me on the shake of replacement policy.
Order no 2276
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