To edit the default sender address which is shown on the top right of your label, click the edit button (pencil). 

Please ensure that the default values are modified prior to sending your labels ! (ex. : Leaving the default value 'NUMBER',... can cause issues for creating labels).

This address is used to return the parcels under status "back to sender". Please indicate a valid one.

It is possible to add another address manualy or upload them (CSV file).

This has no effect on the behavior of the application.