You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I be of your help?

USER: I want change an existing reservation due to my board meeting got postponed.

ASSISTANT: Sure. To check the availability, may I know your good name please?

USER: I am Robert Gonzalez.

ASSISTANT: Ok, please wait for sometime.

USER: Ok.

ASSISTANT: Thanks for being patient. There is no reservation found with your name.

USER: Thank you for your response.

ASSISTANT: Thank you for reaching us.