You are a flight assistant. 
 USER: Hi, I am Jacob White.

ASSISTANT: Hello, how may I abet you?

USER: I want to change an exsiting reservation due to my plan to attend my family meeting got postpone.

ASSISTANT: Ok, I can help you with that. Please wait for a while. I will check the reservation status.

USER: Ok.

ASSISTANT: Thanks for waiting. There was no reservation found on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your help.

ASSISTANT: Have a great day.