Welcome to the Community page,
What is the bank you are with that you are trying to connect to?
Are you doing this on the app or the web browser?
On the app and natwest
Can we ask is it an apple device you are using.
If so can you try one of the steps and one of them should resolve your issue?
Steps to try make it work
• Complete an NVRAM reset (contact Apple support or search for the process)
• Reset the router
• Use a different network
• Use a non Apple computer