Payment using Amex Card keeps on declining

[RainZetroc]

I I have enough available credit to pay but it keeps on declining. I dont know where i can find the 4 digit code and i already contacted my bank regarding this issue they keep on telling me to call the merchant, i cant find any good phone number to reach the merchant. I have to settle my payment asap. Any advise for this? thanks much

[MariMendiola]

The four digit code on AMEX cards is right above the last numbers of the credit card. Mine are small whitish numbers.