Where to sell old phones or laptop?

Don't say olx or stuff, I need some genuine platform where I put details of my device, press the sell order and the platform itself pick it up. Don't want to deal with any individual.

Consider like , when you try to buy mobile or laptops on Amazon or Flipkart, they provide facility to exchange with old item. Same type of platform I want where I don't need to buy anything in order to sell.