Pick the conversation you keep getting wrong.
A live call with someone who talks back and holds things back. You're scored on what you got, not how you sounded.
Build your own
Describe a conversation you or your team actually have. You'll get somebody to have it with — including the things they won't tell you until you've earned them.
The more you know about what this person is privately thinking, the better this gets. That's the part that makes it an exercise rather than a chat.
This decides what it's scored on — a discovery call and a de-escalation are judged on completely different things.