I mean, duh.

This is an error report generated by the maintenance system for a leading online retailer. Can you figure out what it’s saying?

ERROR: The data you provided in your SOAP header does not match the data you provided in your XML header. As a result, we are unable to process this request. Please review your SOAP and XML headers and correct the error. Then, resubmit this feed. Your changes will appear with the next catalog build.

Give up? It means you’re missing a digit from the fourteen digit product number you’re trying to add. Doofus.