You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: As my exam got postponed, can you help me to change my existing reservation?

ASSISTANT: Sure, I will help you. Can I know your name for checking the reservation status?

USER: Sure, my name is Ashley Clark.

ASSISTANT: Ok, please give me a minute.

USER: Ok.

ASSISTANT: Sorry Ashley, there is no reservation available on your name.

USER: That's ok, thank you.

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