You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you now?

USER: Can you please help me to change the travel dates in the past ticket?

ASSISTANT: Sure, I am happy to help with that.

USER: Thank you.

ASSISTANT: Can I have your good name please to check your reservation status?

USER: My name is Nancy Parker.

ASSISTANT: Ok, please wait a moment.

USER: Ok, take your time.

ASSISTANT: Sorry Nancy Parker, no reservation has found under your name to change.

USER: It's ok, not a problem. I think the ticket is not reserved properly. Anyways thank you for your time.

ASSISTANT: Thank you for choosing  us, have a good day.

USER: Most welcome.