You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Raymond Smith here.

ASSISTANT: What type of service you are expecting from us?

USER: Due to sudden health issues, I am not able to travel in a flight on those date that I want to travel. So, I would like to change my reservation. Can you please help me out with that?

ASSISTANT: Sure, I am glad to help you with that.

USER: Thank you.

ASSISTANT: Please wait for a minute.

USER: Sure, take your time.

ASSISTANT: We are regret to inform you that, there is no active reservations on your name in our database.

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

ASSISTANT: Thank you for consulting us. Have a nice day.