Market issue

[dtg755]

I had downloaded soundhound infinity from Amazon app store as the faotd a while back but I'd rather have it through the market so I don't have to maintain two app stores. It's 10 cents today but the market shows it as a purchased app already. The problem is, every time I try to download it tells me I haven't purchased it. I uninstalled it and the amazon app store and cleared cache and data on the market and it still won't let me download... Any ideas?