You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any help from us?

USER: I am Thomas Moore want to visit IAH, can you book a ticket from ATL?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: Sure, my travelling dates will be 07/26 and 07/28.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: That's ok, thank you.

ASSISTANT: You are welcome.