I had a negative experience using my Amex card today. I was buying a big ticket item (in the thousands of ringgit) but I couldn't complete my transaction at the store after 3 attempts. After switching to my Mastercard, I had no problems with completing my payment.

The Cashback and 5xTP were one of the main reasons I chose to have the Amex card in the first place but if I can't take advantage of these two features, what's the point?

I'm going to lodge a complaint to see if I can get the remaining TP that I am owed.

I used the same terminal for both Amex and MC. Amex payment didn't go through but MC transaction was successful.
How is that a terminal issue?

To the guy that said if the merchant accepted Amex, yes they did and still do.

I just used AMEX on Paypal for transaction in Japan Yen.

How much is the additional service charge, 2.5%?