Originally Posted by
garykung
To say Vayama making up their own rules is a overkill.
I would say your best course of action now is to obtain the fare rule of your ticket. The fare rule pretty much defines everything.
In general, to minimize any fees related to changes, the same fare class has to be available first. So given your post contains virtually no useful information, you are basically on your own, unless you can provide further detail.
This, with a further twist. In addition to the CX fare rules, Vayama may have a refund / change policy over and above what CX imposes.
To answer the question of whether Vayama can make up what it wants, it may not. Rather, OP chose to enter a contract with Vayama and those are the rules.
Rather than relying on what some random agent told you on the phone, I would spend the time to carefully review the fare rules and then Vayama's rules and figure out what is best and doable under the circumstances.
The result here is entirely possible and it may well be cheaper to purchase a new ticket back to the US in Y rather than pay for a change and reissue. But, no way to tell without a review.