You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Sure, I am here to help you. May I know your name?

USER: Mary Martin here.

ASSISTANT: Please wait for a while, I will check the reservation on your name and get back to you.

USER: Sure.

ASSISTANT: Thank you for waiting, There was no reservation found on your given name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for opting us.