Online exchange experience felt odd

Need some opinions on this.

I tried exchanging my 4-year-old Redmi Note 10S while ordering a new phone from Amazon. The phone is in decent condition, just a few minor scratches and normal battery wear.

Amazon's estimate showed up to ₹4,000, so I expected around ₹3,000 after inspection. But when the delivery guy checked it, he said they'd only give ₹1,500. I refused, and he suggested either paying the full amount or canceling the order and reordering without the exchange.

The next day, I checked with a few offline stores, including Samsung and Reliance, and most of them offered around ₹3,000 for the same phone.

So I'm confused. If local stores can offer ₹3,000 and still make a profit, why would the exchange partner value it at only ₹1,500? And if they're really firm on ₹1,500, why do they seem so quick to suggest canceling and reordering? Wouldn't that just cost him free ka petrol anyway

Has anyone else experienced something similar?