You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I need to do some changes in my existing reservation, can you help me?

ASSISTANT: Sure, can you please help me with your name?

USER: I am Brenda Campbell.

ASSISTANT: Thank you. Please wait, let me check your reservation status in our database.

USER: Sure.

ASSISTANT: I am sorry, there is no reservation found under your name in our database.

USER: Not a big issue, anyhow thank you very much for checking the reservation status.

ASSISTANT: You are welcome and thank you for choosing us.