I have the same situation too when using my Maybank amex cc to buy item from Amazon US, amazon keep rejecting the payment. But using it in local US store is fine.

What I did was calling the CS (Within 24 hours of the rejection) so that CS could find the rejection record and they specifically allow future transaction for that merchant only. They also asked me how long i will be staying in the US, which make me assume there is a time limit for the merchant allow for my card.

I also asked the CS if it's possible to allow all merchant future online transaction, and they told me this is not possible due to security reason.

This is kind of annoying for frequent traveler to call up CS every time for a new online merchant, plus the roaming fees you need to pay when calling CS in Malaysia from oversea country.

Could you ask CS to enable for online merchants prior to making the payment (Like before you went oversea, and calling CS from Malaysia)? If so, what information the CS required to enable it? Merchant's url? Merchant's name?

I once asked, they need me to at least tried to make the payment once for rejection, so that they could see in their system to whitelist it. Transaction must be within 24 hours of calling CS.

One thing I also noticed that, Amex and Visa has different security measurement for oversea online transaction. I could easily use my Maybank Visa CC for Lyft ride but never on Maybank Amex CC (Maybe I need to call CS to enable, didn't try that).

This post has been edited by hong823: Dec 27 2017, 10:25 AM