You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I have changed my trip details. So will you help me to change my existing reservation?

ASSISTANT: Could you please provide your name to proceed further?

USER: My name is Sharon Williams.

ASSISTANT: Sorry, there is no reservation found under your name. Thank you for reaching us.

USER: Its ok, thank you for searching.

ASSISTANT: Have a nice day.