Why customs entries keep bouncing back before the filing is even reviewed

01A gate that sits before the filing, not beside it

Certain import and export goods are listed, by tariff code or statistical code, as requiring their e-permit or e-certificate to be linked through the National Single Window before customs entry data can be submitted. This is a gate positioned ahead of the entry filing, not a second track running in parallel with it. If the permit has not been linked first, the entry gets rejected once it reaches the system's permit-data verification step — what shows up on the filer's side looks like "the entry keeps getting bounced back," but the actual blockage is the missing linkage, not a mistake in the entry fields themselves.

02Check here first if the same shipment keeps bouncing

If the same shipment is repeatedly rejected and the documents and fields have already been checked with nothing wrong found, confirm first whether that tariff line has been placed on the mandatory linkage list, and whether the linkage was actually completed before the entry was filed — this is the step that is easier to overlook than re-checking the entry fields all over again.

03The linkage list changes, and additions and deferrals have to be read together

Which tariff lines require linkage is published separately by different regulators, and the list moves over time — some notices keep adding items to the existing list, while later notices defer some of those same items instead of enforcing them straight away. Whether a tariff line is currently actually required to be linked cannot be judged from the latest addition notice alone — a later notice may have carved it out or pushed it back. Reading only the addition notice risks an overly strict conclusion; reading only an older list risks missing items added since.

Where this lands in practice: for goods that require a permit or certificate, it is worth confirming the current list with our advisers before every filing rather than relying on a check done last time — this kind of list is revised fairly often.

04When the system itself is down: three fallback routes

When a failure at customs, at the data transmission service provider, a communications outage, or a power failure makes normal electronic filing impossible, the fallback procedure runs on two levels. A failure at headquarters level must be broadcast to the relevant trade associations within one hour by phone, email or SMS, and published online; a localised failure at a particular checkpoint (its own power or communications outage, for example) lets that checkpoint's officer-in-charge decide to switch to the fallback procedure without waiting for the head-office broadcast.

• Emergency paper filing: during a declared failure, filing can switch to a paper entry with supporting documents such as the bill of lading and commercial invoice attached; the entry and every attachment must be signed, submitted in duplicate to a designated service point, and no system data-entry fee is charged in this scenario.
• Counter service: this is not failure-specific — it is a permanent second channel. The importer or exporter hands documents such as the commercial invoice to the counter, the counter enters the data under its own electronic signature, and the system issues the entry number as usual once verified. The counter prints the paper entry in duplicate for the filer to check and sign, returns one copy to the filer, and files the other copy together with the attachments in a monthly batch.
• The permanent paper channel: available regardless of any system failure, with its own format and process; a simple way to spot this type of entry is a handwritten red-ink entry number in the top-right corner — its presence means the paper channel was used, not that the system generated it directly.

Responsibility does not shift with the channel: the counter uses its own electronic signature, but checking the content and signing the entry and its attachments remains the importer's or exporter's own job — an entry error, once signed off, stays the filer's responsibility and cannot be attributed to the counter afterwards.

05A suggested order of checks

When the same shipment keeps bouncing back, check the permit linkage status first, then go back to the entry fields. For goods that require a permit or certificate, confirm the current list with our advisers before every filing rather than relying on a prior check. When the system is down, confirm first which of the three routes — emergency paper filing, counter service, or the permanent paper channel — applies, since the paperwork and retention requirements are not identical across the three. Whichever route is used, the checking and signing step cannot be skipped.

Whether a specific tariff line is currently on the mandatory linkage list, and which fallback route is available at a given time, needs to be confirmed by our advisers against the official notices in force and the actual shipment documents.