You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to change my recent reservation. Can you help me?

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: My name is Charles Davis.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: No issue, thank you for your time.

ASSISTANT: Thanks for contacting us.