You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Benjamin Carter.

ASSISTANT: How may I assist you?

USER: As my exam is postponed, I want to change my recent reservation. Can you help me?

ASSISTANT: Sure, I can help you.

USER: Ok.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: There is no reservation found on your name.

USER: No issue, thank you.

ASSISTANT: Ok, thanks for reaching us.