my monzo bank link has stopped working, i have deleted and re-added multiple times and am just getting a connection error message.

Welcome to the Community, callum.
 

Thanks for sharing what you’ve already tried. When a bank feed suddenly stops working and shows a connection error, it’s often related to how the browser session or the bank’s authorization.
 

To start, try accessing QuickBooks Online in a Private or Incognito browser window. This allows you to use QuickBooks Online without stored browser data and helps determine whether the issue is related to the browser session.
 

Chrome or Edge: Ctrl + Shift + N (Windows) or ⌘ + Shift + N (Mac)

Firefox: Ctrl + Shift + P or ⌘ + Shift + P

Safari (Mac): File → New Private Window
 

From the private window, open QuickBooks and attempt to reconnect the Monzo bank feed.
 

Should the issue continue, try opening QuickBooks in a different supported browser (such as Edge or Firefox instead of Chrome) to rule out browser-specific behavior.
 

If the connection error still persist after trying both options, I recommend contacting Live Support during their available hours, as they have the tools needed to review the connection in more detail and investigate the root cause.
 

Here’s how to contact support:
 

1. Select the Help (?) icon in the top-right corner.

2. Choose either the Assistant or Search tab to get started.

• If you pick the Assistant tab, select Contact a human.
• If you pick the Search tab, enter your inquiry and select Contact Us. Then, choose a way to connect with the right expert.
   

If you have further question, feel free to comment below.