Any help on re authorising hmrc after 18 months I do not seem to be able to get it work

Hi @cookstarling,

Let's get this issue sorted out for you. 

We have an ongoing investigation into this specific situation. I suggest you contact our Technical Support team for further assistance. They can add you to the list of affected users. This way, you'll receive an email notification whenever an update becomes available. 

See this article for the steps: QuickBooks Online Support. Please take note of our Technical Support team's hours of operation, so you know when they're available. 

Let me know if you have other questions about this process of authorising QuickBooks Online (QBO) to connect to HMRC. I'll be around to help you out.