You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

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

ASSISTANT: Sure, please wait a moment.

USER: Ok, take your time.

ASSISTANT: Sorry Campbell, there is a no reservation found on 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 approaching us.

USER: Welcome.