You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Can you help me to change my reservation?

ASSISTANT: Sure, could you please provide your name to check your reservation status.

USER: My name is David Clark.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, there is no reservation on your name in my database.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you for your time.