You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you at this moment?

USER: I am Elizabeth Miller, want to change my recent reservation. Please help me out with that.

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: There is no previous reservation available in your name.

USER: It's ok, thank you.

ASSISTANT: You are welcome.