You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I have made an earlier reservation to attend for a seminar at my university, due to some issues seminar has been postponed. Can you please assist me to change it?

ASSISTANT: Ok, I will help you with that.

USER: Thank you.

ASSISTANT: Ok, may I know your name?

USER: Sure, my name is Ashley Thomas.

ASSISTANT: Ok, thank you for waiting. Sorry, there is no reservation been found to change it.

USER: That's Ok, thanks for your service.

ASSISTANT: Ok, thank you for choosing our agency.