I was checking for this issue ‘The plugin gets stuck on the checkout page, what am I doing wrong?’
As for the new issue, you must check with your bank. Like does the card contain the sufficient amount, is the card valid, does the bank supports this gateway in your country…
This issue is not related to the plugin configuration. The plugin functionality is to load the payment page with the order details, then the bank handle the process at this stage (checks the card..), and after successful processing, the plugin then redirects to the order details page confirming the placement of the order in the website and updates the order status to processing in the orders list.
In your case, the issue is at the level of the bank authentication, that’s why you must check with your bank.