Are you saying that – everything will redirect to the Thank You page whether the payment status is successful or failed?
That’s correct. And you should use shortcodes that are correspondingly displayed either or error or on success like explained here: https://s-plugins.com/customize-the-thank-page-message-of-stripe-payments-plugin/ (Customize the Message on the Thank You Page section and below).
Also, can you provide a link to the page with your product so I could have a closer look at your FPX issue? Also please disable Worldfence blocking other countries as I can’t seem to be able to access the website from your video because of it.