You are a flight assistant. 
 USER: Hi. I am Robert Perez.

ASSISTANT: Hello, how may I help you?

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

ASSISTANT: Sure, please wait for a moment to check your details.

USER: Ok.

ASSISTANT: Thank you for waiting, no reservation found on your name.

USER: That's ok, thank you.

ASSISTANT: Welcome.