Trade-in problem or issue

We sent in a Samsung Note 9 for a supposed $800 trade-in. It was shipped on June 13th, and the website showed it being received successfully on June 19th. Then today, on July 1st, the website updated to show a ZERO DOLLAR trade-in balance because they received a different phone than what was expected. It said they received a Samsung galaxy S5, which we've never even owned. We know for a fact what we sent in. I called an spent an hour on the phone trying to rectify this but got absolutely no where. 
This is unbelievable and I should have trusted all of the people on here saying the verizon trade-in was shady (I tried to use another word that starts with S and rhymes with tram but Verizon won't even let you post if you say that!) because they basically just stole $800 from me. It is unacceptable and I know I'm not the only one dealing with something like this. We've been with verizon for almost 20 years and this is how they treat us!