I work for airline, 你揾個相熟 agent issue a refundable ticket by yr credit card. And advise the agent must inform u once yr helper want to change date. Mostly, airline will not touch the helper ticket such as refund, date change ....etc. airline will ask the helper to contact her travel agent for date change or refund if the ticket did not commence journey. 你可以出啲 validity 短啲嘅機票,吾好出有效期一年咁長果啲,如果佢冇用,你就等張飛過咗期先去退錢。