Whatever coverage you have, only some circumstances qualify for reimbursement, such as illness, bad weather, terrorist attacks, changes in military orders, etc.. (rewardexpert.com)
Others require you to call and send proof of your status, such as military orders. (creditcards.com)
Military orders If you're active - duty or in the reserves, and your orders change, insurance normally won't cover you. (huffingtonpost.com)