You are a flight assistant. 
 USER: Hello. I am Sharon Hill.

ASSISTANT: Hello, How can I help you?

USER: I want to modify my reservation due to preponed of my interview. Can you help me to change my reservation?

ASSISTANT: Sure, Please wait a second.

USER: Sure.

ASSISTANT: Sorry, No reservation found on your name.

USER: Ok, thank you for information.

ASSISTANT: Thank you for availing us.