Fake or not?

Just bought a WD Red Plus 4TB internal drive from a big online dealer. It arrived in a plain box without any documentation, so I checked the serial number on the WD website - the number is correct, but according to Western Digital it relates to a different drive - an APOLLOCR 5400 128M SATA3 6GB/S 4.0 TB 6HD NAS. Have I been scammed?
Thanks, Alex

Seems it’s an OEM part, so all seems to be OK

The last two drives I purchased directly from the WD store both have ongoing registration issues.
(I live in the US and ordered both drives from the WD Store (in the us) )

1 - WD GOLD 8 TB - when registered says ‘out of region’
2 - WD GOLD 10 TB
The following Serial number(s) cannot be registered: because it’s either an OEM product or the warranty has been voided or it may not be a valid product. For further assistance, please contact the WD support team.

raised support incs for both drives.