Hello tony29,
Another thing to check is if the VAT registration number under 'Edit VAT' > Edit settings is the same as the VAT registration number on your gateway account.
If you have confirmed the period and VAT reg no is exactly the same, and you have your confirmation email from HMRC, the next step is to disconnect and reconnect. You can do this by going to the cog wheel > account & settings > advanced. Under here, there should be an option for Making Tax Digital. Select this, and learn how to disconnect. Go through the steps of disconnecting, making sure to follow the link to HMRC's site to remove the authorisation to QuickBooks. Once you have disconnected, click on the same section and 'learn how to connect' - go through these steps then go back to Taxes. Refresh your connection as many times as it takes.
Please let us know if these steps allow you to submit.
Thanks,
Talia
