You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Gregory Robinson.

ASSISTANT: How can I assist you at this moment?

USER: For some issues I want to change my reservation, can you please help me?

ASSISTANT: Sure, I will help you with this.

USER: Sure.

ASSISTANT: Gregory Robinson, 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.