You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Is there any emergency that I can help you out?

USER: I want to change my existing reservation due to some personal issues. Can you help me in changing the ticket?

ASSISTANT: Sure, may I know your name please?

USER: Yes, I am Helen Mitchell.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found for the user name that you have mentioned us for checking.

USER: Ok, not a problem. Thank you for your valuable information.

ASSISTANT: It's my pleasure and thank you for reaching us, have a nice day.