I grouped two rectangles together and can't ungroup them why?

Hello,

I'm new to Corel Draw so please excuse such a basic question but I think I tripped into something out of the ordinary. What I did is I used the rectangle tool to create two rectangles. The first was just a simple rectangle and the second a duplication of the rectangle with a stroke around the area. Then I scaled the second rectangle to be enclosed by the first and grouped them. I scaled them both and decided to ungroup them. However the "ungroup" option under Object -> Group -> ungroup isn't highlighted even though I have the group selected.

Under the Object Manager panel it shows "Group of 2 Objects" as rectangle and rectangle. 

Can someone assist me to understand what is going on?

Thanks

Bill