You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I am looking to change my travel dates in the past ticket because the trip got postponed. Can you please help me?\.

ASSISTANT: Sure, I will help you in changing, please hold on for a moment to check your reservation status. May I know your name please?

USER: Thank you, take your own time. My name is Susan Martin.

ASSISTANT: Martin, there is no any active reservation with your name in my database.

USER: It's ok, thank you for checking.

ASSISTANT: Thank you for utilising our services.