If you don't have the option to print, write your name and the shipping label’s number on the package in clear handwriting and order the package to be picked up via DHL’s schedule a pickup option that you can find here. The shipment of the package is prepaid and you can send it without costs.
Opening the link will show you the following view.
Kindly make the selections as shown on the photo above and insert the WAYBILL-number to it's box as well as your phone number with the correct area code.
Once you have filled up the form, by clicking "Next" you will be directed to a page where you can add all the other information needed for the pickup as well as the pickup time.
The shipping label’s number is the series of numbers under the first barcode (WAYBILL) in the shipping label (see instructions for it here).