Your question is Restore Accountability for Missed Deadlines. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You are leading a cross-functional initiative and one key stakeholder repeatedly misses agreed deadlines, creating downstream delays and uncertainty for the rest of the team. The work still depends on their input, but informal reminders have not changed the pattern and the project is starting to slip.
How would you ensure accountability in this situation while keeping the project on track and maintaining a productive working relationship?