Unfortunately, it's not possible to change the pickup appointment once it's been scheduled. If you're unable to arrange pickup at this date you have two options:
1) Bring your return to a DHL office and hand it over to one of their staff members. Please make sure to hand them the three copies of the proforma invoice. Note: Do not place these inside the box.
2) Submit a new return request in order to book a new pickup date. In this case, be sure to print new documents, as the old ones will have expired.