The most likely reason an employee is not terminated in PeoplePlanner after being marked as a leaver in SelectHR is that the termination reason or reason for leaving is not mapped correctly.
You can check/set the mapping by following the steps below.
In the Employee zone, click Lookups.
Click Employees, then Reasons for Leaving.
Select the Reason For Leaving assigned to the employee you have made a leaver.
On the resulting screen, if the DataHub Mapped Leaving Reason drop-down is empty, use the drop-down and select an option to map the reason for leaving to.
Click Save.
You will now need to resend any records which may have errored. You can do this by adding a space after their initials in their Person Details record.
If the employee is still not being terminated in PeoplePlanner, please raise a new case online and reference the title of this article.