You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

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

ASSISTANT: Sure, may I know your name for the changing process?

USER: Thank you. My name is Jack Harris.

ASSISTANT: Thank you, please wait for a while.

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

ASSISTANT: Sorry, we couldn't find a reservation on your name to change.

USER: It's ok, not a problem with that. Thank you for your time.

ASSISTANT: welcome, thank you for reaching us.