You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How may I help you?

USER: My name is Jerry Walker.

ASSISTANT: Ok.

USER: Owing to an emergency, please change my existing reservation.

ASSISTANT: Ok. Sure, We are here to help you, Please wait.

USER: Ok.

ASSISTANT: There is no reservation found on your name. Thanks for availing us.

USER: Thanks for your help.