USPS support says they can find no errors in my setup.

Hi Preston, 

Customs declarations forms are required for use to APO/FPO/DPO addresses, also known as Military mail. If you are shipping a Military mail package using First Class Mail International, this requires the USPS customs form PS-2976 which states that any shipments with this customs form may not exceed $400 in total declared value.

It's important to report an accurate declared value as that is what will be used to determine duties. If the value is actually below $400, be sure that your customs information reflects this.

However, if the greater than $400 value is accurate, do not lower the declared value beyond what is accurate. Remember, you will also be certifying that your customs forms are correct and posting incorrect information knowingly can have legal consequences.

If you have a shipment worth more than $400, you have a few options for sending it:

1. Ship it Priority Mail Express.
2. Split the shipment. Learn more.
3. Review your item's declared value. If your store provides discounted pricing information for each line item in an order, you can choose to use the discounted product price for each line item on the Customs Form. Learn more.
   

    

Certain APO's do not allow Priority Mail Express.

I've gotten packages returned