You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be your helping hand today?

USER: Robert Roberts here, my exams has been postponed. I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, I will help you. Please wait for a moment let me check and revert to you.

USER: Ok.

ASSISTANT: I have checked in reservation list to change your details, but could not find any reservation with your name.

USER: Not an issue, thank you.

ASSISTANT: Thank you for availing us.