You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you at this moment?

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

ASSISTANT: Sure, I am here to help you with this. Can you please provide your name to check your reservation status?

USER: Sure, the ticket has been reserved on the name Carolyn Hernandez.

ASSISTANT: Wait a moment please.

USER: Sure, I will wait for your response.

ASSISTANT: Carolyn Hernandez, there is no active reservation found under your name in our database.

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

ASSISTANT: Thank you for contacting us.