You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Michael Green, I had done my flight ticket reservation last week but due to raining in that city I want to change my reservation. Can you help me about it?

ASSISTANT: Sure, please wait a moment Green.

USER: Ok.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: It's Ok, thank you for your service.

ASSISTANT: Thank you for choosing our service.