The person appears to be a/an East Asian Male, approximately 20 to 29 years old.
Dear [Name],

I hope this message finds you well. I would like to express my heartfelt gratitude for the invaluable support you provided during our recent project. Your expertise and commitment were instrumental in achieving our goals, and I truly appreciate the time and effort you dedicated to ensuring our success.

Your willingness to go above and beyond did not go unnoticed, and it has been a privilege to collaborate with you. I am grateful to have you as a colleague and look forward to working together on future projects.

Thank you once again for everything.

Best regards,
[Your Name]
Dear [Name],

I hope this message finds you well. I would like to express my heartfelt gratitude for the invaluable support you provided during our recent project. Your expertise and unwavering dedication were instrumental in helping us achieve our goals. I truly appreciate the extra effort you put in to ensure everything was completed accurately and on schedule. It is a privilege to work alongside someone as talented and committed as you. 

Thank you once again for your kindness and support.

Warm regards,
[Your Name]