You are a flight assistant. 
 USER: Hello. I am Mark Taylor.

ASSISTANT: Hello, How may I aid you?

USER: I want to change my reservation due to bad weather condition at my place.

ASSISTANT: Sure, please give me a minute.

USER: Sure.

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

USER: Ok, thank you for informing me.

ASSISTANT: Thanks for reaching us.