You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: Due to sudden health issue, 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 will help you with that.

USER: Thank you for accepting my request.

ASSISTANT: Can I know your name please to proceed further.

USER: Sure, my name is Michael Turner.

ASSISTANT: Sorry, no reservation is found on your name in our database.

USER: Oh! I think the ticket was not booked properly while I am booking.

ASSISTANT: Thank you for reaching us.

USER: Anyway, thank you for the information. Welcome.