Mia angel fertility spells??

Ok so I've been reading up on Mia angels fertility spells and she seems really good! She offers a refund if her spells don't work which sounds reasonable. But what confuses me is if she gives refunds....how does she know the spell hasn't worked for you??? Has anyone ever tried one of her spells or know someone that has? Just don't want to try my luck and get ripped off lol