When you are unable to provide additional documents requested by Customs, this will not necessarily mean your shipment will be returned.
Majority of the time, the documents that Customs will request from you is to help qualify you for potential duty and / or tax relief. When these cannot be provided, Customs may ask for you for alternative documents or clear your shipment with duties and taxes.
In some occassions, Customs may offer to hold your shipment pending the provision of their requested documents. Delivery is then held off until these documents are reviewed and approved, to clear your shipment.
However, there are some instances where the documents that Customs are requesting must be provided else the shipment will be returned. For this reason, we recommend checking with the local Customs authority of the country you are shipping to. They are able to advise what documents must be presented when shipping unaccompanied personal effects via courier service.
Customs is not obliged to contact Sherpr or our customers proactively for additional documents on an order. Each shipment being sent through the network is unique, and it is solely Customs' decision if they wish to offer exemption for your shipment.