HMRC's message · HTTP 400
The request conflicts with the current state of the business ID
When it appears
Changing a business between standard quarters (6 April to 5 July and so on) and calendar quarters (1 April to 30 June and so on).
What to check
- Whether an update has already been submitted for this business in this tax year.
- The period type HMRC currently holds for the business.
How to fix it
Keep the current period type for this tax year and change it from the start of the next one.
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.