You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Anna Martinez.

ASSISTANT: How can I assist you at this moment?

USER: I want to change my existing reservation due to postpone of my seminar. Could you please help me?

ASSISTANT: Sure, I will help you with this. Please give me a moment to check your reservation status.

USER: Sure.

ASSISTANT: Anna Martinez, there is no active reservation found your name in our database.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for utilising our service.