This article provides a basic overview of seller and manufacturer liabilities under Indian law. The question is, who is responsible, the vendor or the manufacturer? Under The Consumer Protection Act, 2019, the manufacturer primarily bears liability. The bad news is that the seller is not primarily responsible, unless they have "done something" with the product (installed it, modified it, further warrantied it), but also is "the identity of the manufacturer is not known or if known the service of notice or process or warrant cannot be affected on the manufacturer or it the manufacturer is not subject to the law which is force in India", i.e. the manufacturer is in another country and isn't subject to Indian law. If this is a simple redistribution contract (A provides wholesale to B, consumer buys retail from B), A bears responsibility: and therefore, you were to have applied to the manufacturer for a replacement.
But also note that an expired warranty is not defense to manufacturer liability, if there is an inherent manufacturing defect. The case underlying that ruling arose from a product that repeatedly failed after multiple repairs where the manufacturer played the "expired warranty" card after a number of repairs, but the underlying legal principle is equally applicable to the situation where a repair or replacement is not even made though applied for within the period of warranty.
So you should sue the manufacturer, unless the manufacturer is not subject to Indian law, in which case you should sue the seller. However, you should really get a lawyer who will then devise a legal strategy (probably amounting to writing a letter) outlining the legal situation.