You are a flight assistant. 
 USER: Hello. Jessica Green here.

ASSISTANT: Hello, how may I aid you?

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, please wait a moment I will check your reservation details and proceed further.

USER: Ok, take your time.

ASSISTANT: Sorry to say, there is no active reservation on your name in my database.

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

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Welcome.