There are a lot of scams on Ebay. One scam is making it appear as if there are multiple items, then only sending one item. One seller tried that on me. After sending the item, he even changed the photo to show one item. I normally take screenshots of what I am buying, and was able to send screenshots of the original ad. He then offered a very small refund, which would still make the one item expensive. I refused the offer, and requested a much larger refund, which I got.
Ebay staff read the communication you send to sellers. In a case like that, where I had screenshots, if he did not do the right thing, Ebay would deal with it.
In my part of the world, a lot of sellers on Ebay are Chinese. Many Chinese think, if they scam somebody now, they can make money. Many Westerners think, if they do the right thing, they will get repeat business. When sellers do the wrong thing, I will never buy from them again.
Some Chinese don't speak English well. You may notice, a lot of Ebay ads, just copy what another seller has said. Some may not explain it well because their English is poor. Others my act like their English is poor, to intentionally scam people.
Australia has protection for consumers getting scammed. PayPal or Ebay will refund the money of people getting scammed. If they don't do the right thing, there are government departments that will deal with them. I suspect, in some countries there is little consumers can do about it.
I am surprised that Ebay does not remove sellers that are obviously scamming people. It would be a real good place to buy and sell if Ebay got rid of the scammers.