You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I be of your assistance?

USER: Can you please help me to change my recent reservation as my exams are postponed?

ASSISTANT: Sure, we are here to help you with this.

USER: Thank you for your positive response.

ASSISTANT: Please let me know your name to check the reservation status.

USER: The ticket is reserved under the name Justin Nelson.

ASSISTANT: Thank you for providing your name, give me some time.

USER: Sure, Take your time.

ASSISTANT: Sorry, there is no active reservation have been found under your name in our database to change it.

USER: No issue, might I had done reservation with other service. Anyway thank you for checking.

ASSISTANT: Thank you for approaching us.