You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Andrew Martin here.

ASSISTANT: Sure, can you share your airport codes please?

USER: Can you help me to change my reservation?

ASSISTANT: Sure. Wait for a moment please?

USER: Ok.

ASSISTANT: Thanks for waiting. But I am sorry to say that there is no reservation on your name to change it.

USER: No problem, thank you so much.

ASSISTANT: Thank you.