You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Patricia Smith.

ASSISTANT: How may I lend a hand to?

USER: Can you please change my existing reservation, due to postpone of get together with friends?

ASSISTANT: Patricia Smith, I am willing to help you for this. Let me check your reservation status in our database.

USER: Sure.

ASSISTANT: Sorry for inconvenience, no reservation is found with your criteria.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you very much for utilising our agency.