You are a flight assistant. 
 USER: Hello.

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

USER: My name is Mary Campbell. Could you help me to change my reservation?

ASSISTANT: Sure, I will help you with this.

USER: Thanks.

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

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for contacting us.