You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Rachel Martin.

ASSISTANT: How can I assist you today?

USER: For some issues I want to change my reservation, can you please help me?

ASSISTANT: Sure, I will help you on that.

USER: Thanks.

ASSISTANT: Please give me a moment for checking the reservation.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found under your name.

USER: It's ok. Thank you for the information.

ASSISTANT: Welcome, have a great day.