The 24-hour rule in KLM allows customers to cancel or change flights without penalty within 24 hours of booking. For more details, call KLM Airlines at 1-833-460-1838 or (+44) 800 208 1075. https://lacdmhowr.powerappsportals.us/forums/general-discussion/dfa47ca8-cfa8-ef11-b542-001dd8097a1a