You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I have planned to change my reservation due to sudden change in my trip, can you assist me?

ASSISTANT: Sure,I wil help you with that. May I know your name please?

USER: Brandon Hall.

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

USER: No problem, thank you for searching.

ASSISTANT: Thank you for reaching us.