You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Amy Johnson here. I want to travel from DC-DCA to TX-HOU, can you please help me to book a ticket?

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: Sure, my dates of journey is from 07/21 to 07/23.

ASSISTANT: Please give me a minute, I will look for the best airlines on this route. Sorry, there is no flight available on your requested dates.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us,.

USER: I will try with the another agency. Thank you for your information.