You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

USER: Linda Rodriguez here. I would like to change my reservation due to business meting, can you help me?

ASSISTANT: Sure, I will help you with that.

USER: Ok, please check and inform me. I will be waiting for your response.

ASSISTANT: I am sorry to say that there is no reservation found.

USER: Oh! That's sad to know. Anyways, thank you for checking.

ASSISTANT: Thank you.

USER: You are welcome.