You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Angela Davis.

ASSISTANT: How may I guide you?

USER: Due to sudden change in plans of my family reunion, I would like to change my existing reservation.

ASSISTANT: Sure Davis, Could please hold on for a moment to check for the reservation details in our portal?

USER: Sure, take your finest time.

ASSISTANT: Sorry, I did not find your reservation on the given name.

USER: That's fine, I think my brother had already cancelled it.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your time.