Hello, @Logibear.

I know how much time it takes when something isn't working the way it used to. I'll help ensure you'll be able to connect Natwest Bank to QuickBooks successfully.

Yes, it's highly recommended to get in touch with your bank or with our QuickBooks Support Team. This way, they'll be able to check and investigate this further. Our support team also has extra tools like the screen sharing session for better assistance.

For the support's contact information, you check it here: Contact the QuickBooks Online Customer Support team.

You can also read the articles listed here in case you have any other banking concerns in the future: Banking for QuickBooks Online.

Feel free to leave a comment below if you have any other questions. I'll be right here to help!