Every carrier runs its own DG approval step before it will confirm the booking, with its own cut-offs and its own form of declaration. The DG declaration has to match the booking and the IMDG class exactly, and a mismatch or a misdeclaration is both a safety failure and a compliance one. It is one of the most common causes of a booking being rejected late.
Glossary
Dangerous Goods (DG)
Cargo classified as hazardous under the IMDG Code (International Maritime Dangerous Goods Code), which assigns each substance a UN number, hazard class, and packing and documentation requirements.