They usually have certified random number generators to make sure the games are fair. If something feels off, like you're not winning as the game rules or RTP suggest, it might be worth double-checking the game's paytable and rules. Make sure you've got the payouts figured out. Sometimes a glitch can mess things up, so it's a good idea to talk to the customer support on the site where you're playing. They can tell you if something's wrong and fix it, or maybe even give you something back if it's their mistake. How responsive they are can also show you how much they care about their players, which is something to think about when you're choosing where to play.