Pre production - El Camino Hospital - Able to add children with same child information (Same SSN)

Login: Employee
Credentials:
User name: thspl9990
Password: Password@3
Company name: El Camino Hospital

steps:
1.Login as Employee
2.Traverse employee workflow
3.Go to child page
4.Enter all mandatory fields.
5.Click on save multiple time.

Actual result: After saving child information, Popup not occur and able to save children with same child information(SSN)
Expected result: Child with same SSN should not be added.

PFA