It's easy: Click the appropriate button at the top of your dashboard, e.g. "Report service matter", and search your active leasing agreements for the desired agreement.
If you find the agreement in your dashboard, all the necessary information, e.g. frame number and lease period, already filled in.
If the leasing agreement does not come from you, you can search for the agreement number and thus get all the information.
This agreement number can be found in the customer's portal or in the customer's mailbox. You then follow the steps in the portal.