You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Can you please help me to change the details in the past ticket? Because the meeting which is held at Austin is changed to Phoenix city. So, I need to change the airport codes.

ASSISTANT: Sure, please share your good name.

USER: Thank you. My name is Sharon Hall.

ASSISTANT: Please hold for a while.

USER: Ok, take your time. I will wait for your response.

ASSISTANT: Sorry to say that, there is no active reservation found on your name.

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

ASSISTANT: Thank you for reaching us.

USER: You are welcome.