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

ASSISTANT: Hello, by what way may I aid you now?

USER: As my plan to go for a holiday trip got postponed, I need to change my earlier reservation.

ASSISTANT: Ok.

USER: Will you help me with that?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Thanks for waiting. Sorry, we found that there was no reservation on your name.

USER: Ok.

ASSISTANT: Thank you for opting us.

USER: Thanks for the information.

ASSISTANT: Have a pleasant day.