You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Nicole Baker.

ASSISTANT: How may I guide you?

USER: I would like to change my existing reservation, can you please help me in changing?

ASSISTANT: Sure, I am glad to help you. Please give me a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found for the user name in our back end to help you out.

USER: Ok, no worries at all. Thank you for your information.

ASSISTANT: You are most welcome and have a nice day.