Dear [Name],
Thank you for the update and for the opportunity to speak with you. I truly enjoyed our conversation and learning more about the role.
If you’re open to it, I would really value one brief insight from you: which aspect of my characteristics was not aligned with the team?
Even a short note would be extremely helpful for me as I continue improving and applying for similar roles.
Thank you again for your time, and I hope we may have a chance to connect again in the future.
Best regards,
[Your Name]

Không dùng câu hỏi mở kiểu “how my profile may not be the best fit”. Đừng khiến người đọc phải NGHĨ. Hãy giúp họ trả lời email nhanh nhất có thể. Ví dụ khác “which technical experience I did not have to fulfill the task” hoặc “what aspects of my profile that was not matched”.