I keep scrolling down for Lightning Experience Rollout Specialist superbadge where it says "Ready to Tackle This Superbadge?
Get hands-on with your Developer Edition org
As in other challenges, you’ll be doing your work in a free Developer Edition org (DE). Use a new DE to avoid unnecessary challenge errors.
amrita.jain.dev@appirio.comLaunchHands-On Org Help
Complete each challenge to earn your superbadge"

But there are no challenges. Though I could find them earlier.

I'm trying to create a new playground, but am unable to do so.  When I try to select create new trailhead playground, nothing happens.  The list doesn't even register that my curser is hovering over the options in the list.  What am I doing wrong?