You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Can you please help me in changing my reservation?

ASSISTANT: Sure, may I know your name?

USER: I am Donna Martinez.

ASSISTANT: Please give me a moment to check your ticket status.

USER: Ok.

ASSISTANT: Sorry Donna Martinez, no reservation is available by your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.