You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I give assistance to you?

USER: I would like to change an existing reservation due to an emergency, can you please help me?

ASSISTANT: Sure, I am glad to help you to change it.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Sure, my name is Dorothy Wilson.

ASSISTANT: Ok, please wait for a couple of minutes.

USER: Sure, I will wait.

ASSISTANT: Thanks for waiting, there was no reservation found on your name to change it.

USER: Ok, not an issue.Thank you for your information.

ASSISTANT: Thank you for availing our service.