Hi,

I've already submitted a VAT return via SAGE to HMRC but as this period is now mandatory, I have to authenticate in order to submit my VAT return for this quarter. When I attempt to authenticate, the authentication fails. I then applied to submit MTD VAT returns via the HMRC site but when entering my company registration number HMRC returns with the message 'The company number you entered is not on our system'. I've double checked and my company number is definitely correct.

Any idea where I may be going wrong here?