Customs declaration and verification form are documents used by the state to supervise import and export trade and foreign exchange receipts and payments. The information filled in these two documents comes from commercial invoices, packing lists and bills of lading. Therefore, when the actual quantity of exported goods changes, the first thing that needs to be changed is the invoice, packing list and bill of lading, and then the relevant contents of the customs declaration and verification form. If the relevant contents of the customs declaration form, verification form and bill of lading cannot be changed at the same time, it will lead to the problem of inconsistent information on subsequent tax refund and settlement.