You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Nancy Martin here.

ASSISTANT: How can I assist you?

USER: I want to make few changes in my existing reservation, can you help me please?

ASSISTANT: Sure Martin, please wait a moment.

USER: Ok, take your own time.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: No issues, thank you for checking.

ASSISTANT: Thank you for approaching us.

USER: Most welcome.