Unable to add card to my Apple Wallet

I can’t add my card to the wallet. It’s just showing a dialog box with ‘Learn More’ button on it. Could you help me solve this issue?

I was in the UAE region first. Then I realized that we can’t use Apple Pay in that region, I changed my region to United Kingdom where Apple Pay is valid. I reinstalled the wallet app as well. But the issue is still there.

[Re-Titled by Moderator]