I once thought "Amazon refurbished" was a program by Amazon...
Turns out they just throw that label on random companies that refurbished on their own.
Bought a cellphone from one, they sent me the wrong phone model, and I paid for unlocked and they sent me one locked to a different carrier, then said that carrier was the most popular (it's not) and they assumed it was what I wanted.
When I was complaining about that, they told me all I had to do was put it in a UPS drop box, explicitly told me I didn't have to go to a store.
According to them, they never got the return.
I talked to Amazon, and their customer service just flat out lied and told me they could see the return was in transit.
Weeks later Amazon tried to charge me for the phone, and I had to do a charge back. Because apparently following the sellers instructions to put it in a drop off, meant I couldn't prove I mailed it.
I have no idea if I was sent the wrong phone intentionally as a scam where they were always going to say they didn't get the return, but it definitely felt like it by the end of it