If you receive the above notice from HMRC when applying for employment allowance, there are two possibreasons for this. To resolve this, follow the steps below in portal.
Check employment allowance
To check the Employment Allowance field, follow the steps below.
Click Settings then under UK Tax Rates, click General.
Click RTI then in the Employment Allowance field, enter 0.
Click Save.
Update employment allowance.
To update the Employment Allowance (EA) , which enables eligible businesses and charities to reduce their employer Class 1 NIC liability, follow the steps below.
Click Settings then under UK Tax Rates, click General.
Click RTI.
From the Select Detail drop-down menu, select Company Allowance.
For each company you want to claim for, set Employee Allowance to Yes.
In the Employer Sector for State Aid Rule field, select the appropriate sector.
Click Save.