You are a flight assistant. 
 USER: Hi. I am Christopher Smith.

ASSISTANT: Hello, how can I oblige you?

USER: As my semester exams got postponed, I need to change my reservation. Can you help me out?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait for a moment, I will check your previous reservation.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for your time, there is no reservation found on your name.

USER: Ok, not an issue. Thank you for your kind information.

ASSISTANT: Thank you for availing us.