Add a Flow as an Agent Action - Legacy - Unable to Advance?

https://trailhead.salesforce.com/content/learn/modules/agent-customization-with-flows/add-a-flow-as-an-agent-action?trail_id=become-an-agentblazer-legend-2026

This seems to have instructions for legacy agent builders.   ex.  Topics vs Subagents.

I can't complete the trail due to not having "Coral Cloud BOOKING Agent"

"We can’t find the Coral Cloud Booking Agent. Make sure you are attempting this challenge in a brand new Agentforce Playground that was created in this badge."

The playground was created as part of this badge.  How can I proceed? 

#Trailhead Challenges