You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Due to urgent work, I would like to change my reservation to some other date, can you please help me out with that?

ASSISTANT: Sure, I am here to help you for this. May I know your name please?

USER: Thank you, I have done it on the name of Jonathan Hall.

ASSISTANT: Sorry, there is no reservation with your name.

USER: Oh! I think the ticket was not booked due to server issue. Anyway, thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: Welcome.