若干月前在jetstar上买了一张票（十月六号杭州去新加坡 3K382），含税1448RMB，starter type, Economy cabin

这段时间计划有变，打算把这张票改签成十月26号同一趟班机，发现需要多加200元（显示26号票价1648元），另加190元手续费，就是390.

而我在Jetstar官网上直接查询得到的票价竟然只是1248元，也是starter type，Economy cabin（这两天涨了，但是也只是1448，跟我的原来票价持平）。

打电话问call center求说法，得到的回复是：我之前买的6号的票虽然也叫Economy cabin，但是是细分票价的M等级，而26号1248的这个票是Economy cabin的E等级。我如果要换时间的话，只能换到26号M等级的票。虽然M等级的票在网站上没有显示，但是他们的系统里有价格， 就是1648元。

我想问，有比这更无赖的解释吗？我已经接受了fare rule里面关于高票价换去低票价不退款的条件，现在要我在已经买的高票价基础上再多付无厘头的200元人民币，我觉得万万不能接受。

这两天打电话跟call center也没有说出结果。钱不多，但是咽不下这口气。请问钟律师我可以怎样对付jetstar的这种行为呢？谢谢

下面附上Jetstar的fare rule关于fare difference这一段

Fare Difference applies per passenger, per flight. Your new fare will be at least the amount of the fare you originally booked and may be more. You cannot change to a lower fare. No refund will be applicable if a lower fare is available.
Fare Difference is the difference (if any) between the fare or fare with bundle originally booked and an available fare or fare with bundle on the date of change which is at least the same fare or, if the same fare is not available, the next available higher fare. The Fare Difference may be substantial.

http://www.jetstar.com/sg/en/planning-and-booking/fares/fare-rules