The message can occur in any tax month and happens if you submit your employer payment summary (EPS) late.

You must submit your EPS after you pay your employees for the tax period, but before the 19th of the next month.

• If you're submitting your EPS late, you should contact HMRC.
• If you don't think you're submitting your EPS late, you should check you've entered the correct tax month in the EPS.