You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Emma Mitchell.

ASSISTANT: How may I help you?

USER: I would like to change my existing reservation, could you help me out?

ASSISTANT: Sure, please wait a minute.

USER: Sure, take your time.

ASSISTANT: There is no reservation found under your name.

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

ASSISTANT: Most welcome.