You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I address you?

USER: My mother retirement function got postpone, Can you do the changes in existing reservation?

ASSISTANT: Sure, let me know your name?

USER: I am Debra Clark.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, no reservation found with your name to change the reservation.

USER: No problem. Thanks for the quick reply.

ASSISTANT: Thanks for availing us.