You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Frank Scott here. 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: Yes, I am here to help you with that.

USER: Thank you.

ASSISTANT: Can you please wait a minute?

USER: Sure, take your time.

ASSISTANT: Sorry to inform you, there is no reservation found with your name.

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

ASSISTANT: You are welcome. Have a nice day.

USER: Welcome.