You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I would like to change my existing reservation, please help me out.

ASSISTANT: On which name can I change your reservation?

USER: My name is Laura Rodriguez.

ASSISTANT: I am sorry no reservation found on your name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.