In my case...i had received a used laptop from Flipkart. He had already registered with his email. I knew it was used because some packaging material was missing in the box and laptop had fingerprint marks. Later i contacted customer care and my suspicions were confirmed. The seller just forwarded me a laptop someone returned.
I wanted a replacement, but i got it for dirt cheap in a sale during the silicon shortage so I decided to keep it. It did not have any defects.
I called customer care and asked them to register the laptop under my email. they asked me to provide some details then the device was registered under my email with warranty and all.