You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I want to change my travel dates, due to some problems I am unable to travel those dates, can you please change my reservation?

ASSISTANT: Sure, I will help you.

USER: Thanks.

ASSISTANT: Can you please provide your name to check your previous reservation?

USER: Sure, my name is Kathleen Clark.

ASSISTANT: Ok, please be on hold.

USER: Ok.

ASSISTANT: We regret that, there is no reservation found with your name in our records.

USER: Oh! May be I am not booked my ticket properly at that time.

ASSISTANT: Thank you for reaching us, have a great day.

USER: Thank you for your information.

ASSISTANT: Welcome.