You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Andrew Adams.

ASSISTANT: How may I assist you?

USER: I want to change my existing reservation due to postponed of my project submission dates. Can you please help me with that?

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: There is no reservation found with your provided name in our data base.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for choosing us.