Stuck on "Add a Flow to Your Prompt Template" – "We can’t find the New Guest Newsletter prompt template activated"

Hi Trailblazers,

I am facing an issue on the challenge "Add a Flow to Your Prompt Template" under the Quick Start: Create a Prompt Builder Flex Template project.

Error Message: "Step not yet complete in Einstein AI. We can’t find the New Guest Newsletter prompt template activated."

What I have already verified/tried:

• The prompt template "New Guest Newsletter" (API Name: New_Guest_Newsletter) is saved and Activated.
• The Template-Triggered Prompt Flow (Get Experience Newsletter Data) is activated and properly referenced inside the prompt.
• The Preview works as expected and generates the output correctly.
• I have tried in second Playground and completing everything from scratch in the new org, but the error persists.
• Tested multiple versions of the template, deactivating and reactivating, yet the issue persists.

Has anyone found a workaround for this, or is this a known issue with the verifier backend? I need help on this.