iTunes Producer invalid price

I'm trying to publish my book on the Apple Bookstore through iTunes Connect. When I set price, it's fine for the Americas but I'm being told the price is "invalid" for Europe. It doesn't tell me what it is wrong with it, and when I try to set to other prices (including the listed tier prices) those get rejected too. My base price in the US store is $2.99 (which is valid), how do I know what to set it to in the UK and Europe?