You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I am here to help you with that. Can you please share your name?

USER: Emily Lewis.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name in our database.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for opting us, have a nice day.