You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Kathleen Robinson here.

ASSISTANT: How may I help you at this moment?

USER: Due to sudden change in my planned date of journey, I would like to change my reservation. Can you please help me out with that?

ASSISTANT: Sure, I am here to help you with that. Can you please give me a moment?

USER: Thank you. Take your time to check.

ASSISTANT: I am really sorry to inform you that, I haven't found any reservation on your name to change.

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

ASSISTANT: You are most welcome. Thank you for reaching us.