You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: My name is Daniel Martinez.

ASSISTANT: How may I assist you, Daniel?

USER: My friends have cancelled the holiday trip. So, I would like to change my existing reservation. Can you help me?

ASSISTANT: Sure, I will help you. Please wait a moment.

USER: Ok, take your time.

ASSISTANT: Sorry Daniel, no reservation has been found on your name in our database.

USER: I think my friends have changed it on my behalf. Anyways, thank you for the information.

ASSISTANT: Thank you for choosing us.