First, get the flight delay certificate of the carrier (the person in charge of the airport or flight), which should indicate the reason and hour of the delay; Then download the claim application form from Meiya official website and fill it out as required; Finally, within 30 days after the incident, the certificate and application will be sent to AIA Claims Center together with the air ticket.
Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.