You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I would like to change my reservation due to sudden plan change in the trip, as our friends planned to go on other dates, can you please help me by changing the ticket?

ASSISTANT: Sure, may I know your good name please?

USER: Kathleen Clark here.

ASSISTANT:  We sorry to inform you that, we did not find any reservation with your name.

USER: Ok, no problem, thank you for your information.

ASSISTANT: Thank you for contacting us. Have a great day.

USER: Thank you.