You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Myself Jessica Johnson. I need to change my existing reservation, can you please help me out?

ASSISTANT: Sure, I am glad to help you? Please wait for a while.

USER: Please take your own time.

ASSISTANT: Sorry, there are no reservation found on your name.

USER: That's ok, thank you for searching the details.

ASSISTANT: Thank you for choosing us.