Basically Kiwi.com is a legally created machine for scamming people hidden behind nice UX experience. They created really compelling and easy to use website, however if there is any change on the side of a airline provider when it comes to your booked flight, they will make you bleed money. They will only let you do changes which will result in then keeping basically 80-100% of originally booked ticket and this is how their business model works. I had to book several flights in advance of several months and I was so unfortunate to have changes in all of them done by airline. And the only options Kiwi.com offered me and allowed me to do would result in me paying basically 80% premium on top of already paid tickets. Hiding themselves behind policies which are not written to cover their risks, but to let them keep the money. (For some of the flights I had flexible ticket package, still they dont care if airline does any change, flexible ticket is not applicable anymore). After doing a bit of research and despite them proactively trying to prevent me from doing so, I have agreed with airlines directly to change my flights which resulted in NO additional payments. So I saved 80% of money just by calling kiwi as a liars. So I suggest to pay always few percent extra or even less customer friendly competitors to Kiwi.com. Being Czech, I am ashamed the company is praised as one of the best tech startups in CZ.