You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: Please help me to book a ticket from IAH to EWR, as I need to attend an important meeting with my client.

ASSISTANT: Ok, can you please provide your travel dates?

USER: I need to travel on 09/18 and 09/20.

ASSISTANT: May I know your name to proceed further?

USER: Yes, I am Larry White.

ASSISTANT: Larry, I am sorry to inform you that there is no flight available at your request.

USER: That's ok, I will try to go in some other way. Thank you for your time.

ASSISTANT: You are welcome. Thank you for contacting us.