'Payment Failed' for Natwest Card Only

Since Friday my Apple Pay has 'Failed' (as per attached image) but only when using the Natwest card shown. The payment fails both on in-app purchases and in store when completing a contactless payments, regardless of vendor. The card itself is fine, has years left until expirey and itself still works for contactless payments. I have been in touch with Natwest and they can see nothing wrong on their end that might prevent the card from working normally with Apple Pay as it has done for years. iPhone is updated to the latest iOS.

Do let me know if more info is needed. Any help is much appreciated.