You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What can I do for you today?

USER: I already book a flight ticket to reach Seattle, but now I want to change my reservation to new journey dates. Can you help me with that?

ASSISTANT: Sure, may I know your good name please?

USER: My name is Michael Williams.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: Ok, thank you for the details.

ASSISTANT: Thank you for reaching us.