You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Williams Walker, I want to change my reservation as my plan to meet my friend at Houston is postponed. Can you change my reservation?

ASSISTANT: Sure, please stand by I will get back you.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry to say no reservation found on your name.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.