You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself William Wilson.

ASSISTANT: How can I aid you at this moment?

USER: I need to do some modifications in my earlier reservation so please help me with changing my reservation.

ASSISTANT: Sure, I will help you with that. Please wait a moment, I will check your reservation status.

USER: Thank you. I will wait for your response.

ASSISTANT: There is no previous reservation available in your name.

USER: Oh! It may not be booked properly while booking due to server issue. Thank you for your time.

ASSISTANT: You are welcome.