The answer lies with the Payment Network Operator (Visa, Mastercard, American Express etc.). When you use the banks app, the process bypasses Apple’s security requirements mandated by the bank.
The information you submit is first sent directly from your iPhone to the PNO for verification and approval. If they approve, it’s sent to the issuing bank for approval. If they approvea a dynamic payment token is sent to your iPhone for use instead of the card information.
In my experience the PNO has found a fraud issue on one of your accounts. The bank needs to work with the PNO to remove the fraud alert. If you contact the PNO, they say everything is fine. They have no way of verifying your identity and the ownership of the device by the account owner.
There is a chance it’s a hardware issue, but the error message would be different. Please have Apple perform diagnostics on your iPhone. It can be done in person at an Apple Retail Store or at an Apple Authorized Service Provider. You can also contact Apple Support and request remote diagnostics.
If you’re in the US please call 1-800-MY-APPLE or outside the US, consult the support articles below.
Contact Apple for support and service - Apple Support
Another remote possibility is the use of a VPN. Are you using a VPN?
If the hardware passes, you’re back to working with your bank.
