You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I want to change my reservation as I have to stay with my brother for some more days at Las Vegas, can you please help me with changing my reservation?

ASSISTANT: Sure, I will help you with this.

USER: Thank you.

ASSISTANT: Can you please provide your name to check your reservation status?

USER: My name is Eric Wilson.

ASSISTANT: Eric Wilson, there is no active reservation found under your name in our database to change it.

USER: Oh! Not an issue, thank you for checking.

ASSISTANT: Thank you for utilising our service.