This requires you to have an individual service (such as a parking space).
Once the individual service has been chosen, you will arrive on your personal calendar.
All the dates indicated by a green light correspond to the days when you can release your service.
Click on the day that interests you and then press on "Release".
When the release is confirmed, the light indicator turns red
You will be notified once the release is confirmed, as well as when another employee reserves your spot.
For more information on the different light indicators, you can consult this article.