Bummer, Fatman. Maybe they transposed a digit in your serial number. I think they should have requested more info so they could verify the information. If you model/caliber didn't match the s/n then they could have asked you to double check. As it is, if the customer or the data entry person gets a number wrong, there's no error detection, until you get the wrong magazine. Maybe they figured that was cheaper in the long run.
Hopefully you'll see them soon.