Amazon - realme Buds Wireless 2 Neo Black Missing from the product Box

I have ordered realme Buds Wireless * Neo (Black) on *th Decmeber the product was delivered on **th December. When the product was delivered i found that the product is empty and the main product, accessories missing then i contacted the customer service of Amazon.in they informed me that they will investigate the issue and they may contact me on or before **th December. Till the time i contact them they didn't contact me. on **th December email was received that they have investigated the issue with the carrier and found that the product was delivered to the customer.
Again calling to the Amazon customer service they are so rude that they are not listening to the customer. They are telling that the investigation is completed and they will not do with this issue anythng after this.
My point is why didn't they contacted me for the verification purpose and when they have decided that they will not do anything on the issue then they would have close the issue asap. why did they wait for * days to show that they are investigating. Really such cheaters are they and they will never be against the seller.