You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

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

ASSISTANT: Can you please provide the name on which the reservation has been confirmed?

USER: Sure, my name is Betty Johnson.

ASSISTANT: Sorry, there is no reservation found by the name that you had provided.

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

ASSISTANT: Thank you and have a nice day.

USER: Thank you for your information.