On Saturday I booked a return flight on the KLM website, London to Amsterdam return. However on Monday I realised that this was a mistake and I could not make the trip, so I called KLM to ask if I could get a refund or change the date. They have said that my ticket is totally non refundable and non changeable. Does anybody know if it is possible to get some partial refund or change the dates ? or maybe I can make a claim against my travel insurance ?