Bajaj Electronics — Defect mobiles

I had purchased redmi note 9 pro max on 6th sept 2020 in punjagutta branch, hyderabad with amazon pay, 20, 500 rupees at a time.
i started using in on 7th sept and noticed that upside speaker is not working and i asked mobiles section manager to replace it with another model as i feel this model having issues, i said i will take 1 day to decide what to take come back to store next day. on 8th sept i went there and asked to give me one plus or iphone as i am ready to pay extra amount and then he said its not possible to change and i have to take same model again. after getting a problem within few hours o[censored]sing mobile is anybody would take same model again?? i asked him to replace with another brand and he said “no, at bajaj we cant, do whatever u want to do, we only can give same model to u again” .

what i have to do??
i given that handset, box, bill to him on 8th sept and told him to take replace for same model as said and take it to home and use it for their family.
regards:
k srinivas
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