Amazon India — cheating with customer

Address:

Kota, Rajasthan, 324005

Worst experience from amazon. I bought red mi 6a mobile rs 6999with replacement term condition. But the proximity sensor of mobile not working. I want to replace the phone during the period mentioned by amazon, but they deny told that product not available u got refund.
But after the next hrs of expiry of replacement same colour, same specification mobile with higher price available to sell.
Means amazon sells damaged product during seasons sell with less price and then not replace.
They cheat with customers
I have talk to many officals of amazo in technical wing mr. Shashikant, mr ranjan and their senior person mr. Saklin m. But they didnot help me.