If the serial on an invoice differs from the watch, resolve it while the transaction is fresh. A typo may be innocent, but leaving it in place can complicate later service, insurance, resale, or a theft report.
Confirm the discrepancy
Compare the physical engraving with the invoice and any manufacturer or service records. Check look-alike characters and make sure you are comparing serial to serial rather than to a model reference.
Ask the seller for a corrected document
Contact the seller in writing, identify the exact invoice and watch, and request a corrected invoice or signed correction that clearly links to the original. Keep both versions and the correspondence; do not edit the original yourself.
Pause if the seller will not explain
A clear transcription error should have a traceable correction. If the seller refuses to acknowledge the mismatch, or the serial appears altered, stop relying on the paperwork and seek independent advice before proceeding.
For a theft-status search, use the verified physical serial. Keep a note that the invoice contained an error and retain the corrected record.
Use the Physical Serial
Confirm the engraving first, then keep the corrected invoice with the search result.