You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Dorothy Anderson.

ASSISTANT: How may I aid you?

USER: I am looking for changing of my recent reservation. Can you help me out?

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Dorothy, there is no reservation found under your name.

USER: That's ok. Thank you for your help.

ASSISTANT: Most welcome.