Newbie challenged. Change RAID not recognizing Volume 2

I have a Ultra EX2, 2 bay, 4 TB each and am attempting to make volume 2 a redundant drive of volume 1. From what I can tell from the fabulous (ehem) instructions: I selected Switch to RAID 1, it self tests the two drives, but when I get to the Configure RAID mode size settings shows Volume 1 (Drive 1,2) but then the last screen for Configure RAID only shows 1 volume to encrypt - I believe it should be showing 2 volumes.
Perhaps this is all semantics and there is actually a copy of my 2nd drive there?

Hello,

Please refer to the following KBA article: My Cloud: RAID Online User Guide and Solutions