You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am Angela Robinson, due to my health issues I would like to change my recent reservation which I have done last week to Denver. Can you help me to change my existing reservation?

ASSISTANT: Sure, I will help you with that, give me a  minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no reservation found on your name.

USER: Oh! It might be cancelled by my mother but she did not inform me yet. Any way thank you for the information.

ASSISTANT: Thank you for contacting us, have a great day.