You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER:  I am Scott Allen want to attend a press conference held at Houston, TX-IAH. Can you please book  a ticket on 10/28?

ASSISTANT: Sure, May I know the source code?

USER: I will depart from Denver,CO-DEN.

ASSISTANT: Please help me with your return date.

USER: My return date is 10/30.

ASSISTANT: Please wait a minute.

USER: Ok.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, no issues. Thank you for your response.

ASSISTANT: Thank you for availing us.