Some external systems don't allow the API keys to access the email addresses of the users doing various activities.  In those systems, if you want employees to have their external system events mapped to their Peoplelogic.ai account, you will need to enter a mapping for the external username.

This can be done during initial setup by importing a CSV, when you add a new employee through the Peoplelogic.ai interface or when editing an employee.  The mapping interface can be found on the final stage of editing or creating a new employee as shown below: