You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Mark Thomas.

ASSISTANT: Thomas, how can I help you today?

USER: I just want to cancel my reservation, can you help me to cancel my reservation?

ASSISTANT: Sure, I am here to help you, please hold on for a moment to check your reservation.

USER: Sure.

ASSISTANT: Mark, I did not find any reservation with your name in my database.

USER: Oh! that is fine. Thank you for your time.

ASSISTANT: It's my pleasure, have a nice day.