You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am Dorothy Phillips, I want to change my reservation as my plan to meet my sister at Houston is postponed. Can you change my reservation?

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for reaching us.