Ebay.ph Kuponan refuses to refund overpayment

I purchased something from Ebay Kuponan last Monday (Ebay's version of Ensogo, Cash Cash Pinoy, Metro Deal, Groupon). I sent my payment via Gcash. I received a message informing me that my payment cannot be completed, so I tried sending the payment again. I received the same message. I tried sending Gcash one last time, again I received the same text. After a few minutes, all three payments were successfully sent. I called up Ebay. They said they'll refund the overpayment the following day (Tuesday). Wednesday came but I still did not receive any call or text from them. I emailed them afterwards, this was the message they sent me:

"Hi,

Good Day.

Our apology for the inconvenience.

We tried to contact the number but it was unattended.

Anyway with regards of your concern sorry to inform you that we are not allowed for any refund as the advise on the management.

We can only suggest you to use the money amount of PHP1998.00 to other Deal since the mistake is with the part of you.

We hope for your understanding as what our policy.

Thank you."

Is it legal for companies to have a no refund on overpayments policy? I'm not cancelling my order, I just want to refund the overpayment I made.

i'd say that's not valid. but if they refuse, your remedy of even just a small claims case might be more expensive than the claim.

Sa above case, pwede bang mag-complain against the company for unconscionable sales practice? If so, where and how?

Concerned din kasi ako kasi I also buy things online. Baka mangyari din sa akin. Though, kung mangyari nga sa akin at kung kung di masyadong malaki ang docket fee, I might go for small claims para at least matauhan ang company at di na nila gawin sa iba.