Hi Rory O'Conor,
To narrow this down, could you let me know where you’re using Copilot, such as in a browser, the Windows app or a mobile app? Does the error happen in every new conversation and does it also occur on another browser or device?
If you’re using a browser, please test Copilot in an InPrivate or private window. You can also temporarily turn off any VPN, proxy, ad blocker or privacy extension and try a different network, such as a mobile hotspot. This will help confirm whether the issue is related to the browser, network or your account.
Please let me know what happens after those tests and I’ll help you narrow it down further.