You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I would like to change my existing reservation. Can you help me in this?

ASSISTANT: Sure, may I know your name?

USER: Patricia Jackson here.

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

USER: Ok.

ASSISTANT: Sorry Patricia Jackson, no reservation is available by your name.

USER: Not a problem, thank you.

ASSISTANT: Thank you for reaching us.