Hi
Apple Pay is available:
On eligible devices, which include iPhone SE, iPhone 6, iPhone 6 Plus and newer iPhone models:
In selected countries:
If you are using an eligible device and are within one of those regions, check that your iPhone region is set accordingly:
On your iPhone, go to: Settings > General > Language & Region > Region.
Also follow all of the required steps here, including ensuring that you are signed in to iCloud and that you have enabled Touch ID or a passcode on your iPhone:
Note that it is only possible to add supported payment cards from participating banks or stores within those countries:
Apple Pay participating banks in Canada and the United States - Apple Support
If you still need help, then I suggest that you contact Apple Support or make a Genius Bar reservation for assistance: