My Cloud Home Duo 8TB not available in Time Machine

Today I purchased and installed the 8TB My Cloud Home Duo. I see the drive on my desktop, I am able to access it via Finder, but when I navigate to Time Machine > Open Time Machine Preferences > Select Disk, it does not appear as a disk to choose. I have attached portable external drives to my MacBook Pro, and they DO appear in the Select Disk list.

Here is additional information that may apply to this issue:
-I have read and followed the online documentation about setting up Time Machine with My Cloud Home Duo
-I have read and followed the Apple instructions linked from the pdf version of the My Cloud Home user guide (downloaded from MyCloud.com)
-I am using a new MacBook Pro running iOS Mojave (10.14.3)
-I updated the firmware on the My Cloud Home Duo when I created my account and connected to the device
-My iOS and all apps are up to date on my MacBook Pro as of February 25
-I updated the firmware for My Cloud Home Duo when I installed the NAS today.

Any help is greatly appreciated. Thank you.

James

@JamesKL you may not have a My Cloud Home because manual download and updating the firmware is not possible on this product. Have you allowed TM backup through your firewall?