Answer:
I dont really know if theres a specific format but I'll do my best
Step-by-step explanation:
Dear Mr. Nam,
This email is to inform you that reservation dt12345 at Duy Tan Hotel (booked under your name) has been successfully canceled. This cancelation is free of charge.
If you did not order this cancelation, please correspond with us immediately. If you did, no further action is needed.
Warmly,
Duy Tan Hotel