For flights to/from EU member countries, Regulation 261/2004 is applicable. I guess Rule 240 would be the US equivalent. It can be tricky to get the airline to

For flights to/from EU member countries, Regulation 261/2004 is applicable. I guess Rule 240 would be the US equivalent. It can be tricky to get the airline to comply when they deny responsibility. So there are intermediary agencies that do the claim paperwork (and take the legal actions if necessary), taking a small percentage of the reward only if successful. With the help of an intermediary, I successfully invoked Regulation 261/2004 against KLM after a flight was cancelled due to mechanical failure. The correct reward was ultimately transferred approximately one year after the original flight. https://www.airhelp.com/en/know-your-rights https://www.airhelp.com/en/know-your-rights