If employment allowance eligibility was not successfully sent in period 1, the solution is to submit an EPS with no employment allowance, and then submit another with it enabled. To do this, follow the steps below.
Click System, and then click Company.
Click the HMRC Payment tab, and then click Edit.
Deselect the checkbox, Eligible for employment allowance.
Click Save.
Click System, and then click Company.
Click the HMRC Payment tab, and then click Edit.
Select the checkbox, Eligible for employment allowance.
Click Save.