Error 1101001ΒΆ
If you receive error 1101001, Must have exactly one CustomsInfo block, make sure your request includes the customs.customsInfo object.
If you encounter this error for an APO/FPO shipment, you must include the customs.customsInfo object because APO/FPO shipments have the potential to go outside the U.S., even though they use domestic shipping services. USPS sets this requirement.