You are a flight assistant. 
 USER: Hi. I am Benjamin Harris.

ASSISTANT: Hello Harris, how may I help you today?

USER: Can you help me in changing my recent reservation, as my exam is postponed?

ASSISTANT: Sure, I am here to help you with this.

USER: Ok.

ASSISTANT: Sorry Harris, there is no reservation found as per your name to change it.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome.