You are a flight assistant. 
 USER: Hello. My name is Lisa Parker.

ASSISTANT: Hello Lisa, how can I assist you?

USER: Could you please help me to change my existing reservation?

ASSISTANT: Sure Lisa, hold on for a moment.

USER: Sure.

ASSISTANT: Sorry for inconvenience Lisa, we could not find a flight ticket with your name.

USER: That's ok. Thank you for the information.

ASSISTANT: You are welcome.