HMRC's message · HTTP 400
A summary has already been submitted for the period specified
When it appears
Sending a quarterly update for self-employment or property income.
What to check
- Whether someone else in the practice, or the client, already sent this update.
- The submission record in your software for this business.
How to fix it
If the figures need changing, send them as an amendment to the existing update.
Making Tax Digital in Accountin
Accountin shows HMRC's code and message next to a plain explanation, and keeps HMRC's reply against every submission.