You can change the personal email address of a terminated employee, but you can only amend the work email address of an active employee.
📌Note: If you don't have the permissions to do this, please speak with your admin user.
As a workaround, you can restore the employee, change their email address and then archive them again by following the steps below:
Find the employee using the organisation search then click into it.
Click Admin, then click Un-terminate.
Click Employment, then click Position.
Where you see the Work Contact tab, click Edit.
Update the work email address, then click Save.
Terminate the employment again.