You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I support you?

USER: Can you assist me to change my reservation please?

ASSISTANT: Sure, on whose you did the reservation let me know to check the list?

USER: Sharon Edwards here.

ASSISTANT: Ok, please wait a while.

USER: Sure, take your time.

ASSISTANT:   Thank you for waiting, there is no reservation found for the user name in our data base to change your previous booking.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for opting us. Hope to seve you again.