Amazon are pretending to sell my book

I have written and self-published a book, and I have a seller account specifically to sell that book. Nobody else sells the book. The only other place where it’s listed is on Nielsen, because you have to list it there in order to set it up as a product on Amazon.

At first Amazon was telling me that I needed to lower my price because there was an “external competitor” selling it for less. I think they were just looking at the price on Nielsen and acting like that was an actual competing retailer.

I lowered my price (what choice did I have?) and now they have added a buy button, but it’s for a “temporarily” out of stock Amazon-fulfilled option and the option to buy it from me (the only real option) is pushed further down.

I’m getting towards the end of my rope. I’ve tried dealing with their support channels (lol).

Is this just the way it works? Is there something I’m doing wrong? Any advice would be extremely welcome. Thank you.