FBA Manufacturers bar codes

Hoping someone else has come across this.

I recently sent in a box of mixed items and had x4 of a certain product which when it came to labeling up was said that the manufacturers barcode will be used.

The box has been in a state of receiving for over a week now with all products received apart from the 4 that didn't need one of my produced barcodes there is inbound 4 received 0, it just seems odd that they're the only items missing.

Anyone else had this?

Thanks in advance.