If the booking or B/L stays the same and only the vessel changes, nothing is required from you.
Dockflow shows the new vessel against the same reference.
A short delay before the new vessel appears is normal. If the carrier’s own page shows the new vessel and Dockflow still shows the old one
several days later, that is worth
reporting with the reference.
Example
A shipper’s booking stays the same, but the carrier moves the cargo to another vessel. The shipper does nothing, and the new vessel appears on the shipment. If the carrier shows the new vessel but Dockflow still shows the old one several days later, the shipper reports it with the reference.