Flipkart — Defective mobile replacement

I had ordered Realme Narzo 50 A Phone on Flipkart and they delivered me the defective product. I had requested them a replacement but they rejected it so many times also I requested a refund /replaced that also they are not providing me. Now 20 days has passed.
Please help me to resolve this issue.

Below are some additional information:-

Ordered Item - Realme Narzo 50 A Oxygen blue, 64 GB
Product Ordered date - 18 Oct 2021
Order Id-OD[protected]

Also, I have attached an Invoice copy of the ordered item.

Regards,
Chya Rani
[protected]