Your question is Root Cause Analysis for Recurring Issues. 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).
Describe your process for uncovering the root cause of a recurring project issue.
Focus on how you would separate symptoms from the underlying cause, validate your hypothesis with stakeholders, and prevent the issue from repeating. Keep your answer practical, with clear steps and decision points.