Where is nine-digit code?

I just received a My Book Duo 8 TB drive. When I try to log in to the WD My Cloud app, I am asked for a nine-digit code from the Quick Install Guide. There is NOTHING resembling it on the little green card that was in the box. Next the app informs me to look at the drive’s serial number label on the bottom of the drive. AGAIN, there is no such code on this label. When I try to get phone support, the request form asks me for my device serial number. When I enter the number on both the box and the serial number label, the form tells me that it is an invalid serial number.
What is going on? I submitted an online case but no reply as yet.
Is this what I should expect for service from Western Digital?

The My Book Duo and the My Cloud Home are 2 different products. The My Cloud home is a network attached storage (NAS) drive whereas the My Book Duo is a Direct attached storage (DAS) drive. Direct attached storage are drives that connect via a USB cable. These drives are not accessible using the My Cloud Home app. the My Cloud Home app only works with the My Cloud home network attached storage product.

if you are trying to get support from the link below, that is only available for My Cloud products. If you have a My Book that would explain why it says the serial is invalid.

My Cloud Home Duo using the WD Discovery app is asking for the nine-digit code. I am still in need of phone support. No other support help make sense to me.

If you have this product, then look at the Quick Start And the Label

Neither of these images match the quick start or label on the WDBFBE0080JBK-NESN MY BOOK DUO 8TB PAN-AM that I received.

You have a My Book Duo (Direct Attached Storage) and not a My Cloud Home.
No code is used for My Book Duo products

As @SBrown said you do not need to use a 9 digit code to set up a My Book Duo. that is only used for My Cloud Home products.

If you need phone support you can contact WD technical support using the general support number listed on the page below.