Good idea, needs work
A technical glitch spoilt the beginning for me: when you start in an imaginary country, you need to locate it firmly in space and time. For the first few paragraphs I knew we were in the present day because of the bus, but I had no idea if we were in a fictitious European country in our own world, or a different universe where the USA is a kingdom. Since the AC is an international event, a few lines to set the geography could be part of Addy's infodump about it, and then we know where we stand. Though in European kingdoms today royalty doesn't have anything like that sort of power (there are Arab kingdoms where the Crown Prince can simply order people sent to jail without a hint of due process, but they're not the benign nation you describe), so you'd also need some explanation of that oddity.
Read the story now
OK, two glitches: it's never clear quite what the AC is, or even what AC stands for. At first it sounds like it's just within Fannelia, then it's international; it has an athletic element, but our characters never take part in that (because they pull out before?) It's a good excuse for a meet-cute, and for forcing your couple to stay together when they fall out, but it needs work.
That said, I kept on reading because it's so refreshing to see a prince-and-pauper romance where the Prince is not a brooding noble hero who takes charge and saves the broken heroine by his manly strength, but (much more plausibly!) a spoilt brat with control issues, who has to be hit over the head a good many times before he even starts to get a clue, and is only just forgiveable because he keeps trying to do right. We need more romances like that!