You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I would like to change my existing reservation, can you help me in that?

ASSISTANT: Sure, may I know your good name?

USER: Sure, myself Jacob Lewis.

ASSISTANT: Ok, please wait for a minute.

USER: Sure, I will wait for your response.

ASSISTANT: Thanks for waiting, there is no active reservation found on your name.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for opting us.