I experienced this recently and filed a dispute with my credit card company about this. Here is what I entered in their dispute form:
Why did you cancel the transaction?
Needed to change flight date, but their system did not apply current fare to new fare. So I had to cancel it. Merchant did not refund any portion of ticket as they promised.
Were you advised of the cancellation and return policy at the time of the purchase?
Yes
What is the cancellation and return policy?
Their cancellation policy is that we would receive a refund minus a 2000 peso cancellation fee. However when I canceled, the remaining portion of my fare after the cancellation fees, went into a 'travel fund' that is very hard to collect. Cheap scam.
Additional details
As you can see, they don't want to give you a direct refund. Instead, they put your refund into a vague 'travel fund' that is difficult and inconvenient to collect. Typical Filipino scam and shell game, designed to allow them to pocket your refund, since they know that most people will not go through the legwork of collecting such a thing. Common sense. It's a low class shady street scam. And it's a shame that an airline would pull such a ghetto trick. Shameless. And unfortunately, very typical of the Filipino mindset as well.