For refund in my flipkart paylater a/c

For refund in my flipkart paylater a/c
I orderd the battery for my mobile phone poco x3 pro on flipkart with my paylater a/c but flipkart delivered me the dead battery and i requested more and more to flipkart for battery return bur flipkart was not picking up my battery neither retun or also not refunded my 1499 rupees. But flipkart customer care gived excuses.
Sir i request you to please help me in this for my money back in my flipkart paylater a/c and return this drad battery.
Sir pls help me because flipkart paylater calls me much and much for their money back.