You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Ruth Williams here.

ASSISTANT: How can I help you?

USER: Please book my ticket from HOU to IAH.

ASSISTANT: Sure, I am glad to help you. Could you please share your travelling dates?

USER: My trip dates are 01/21 and 01/23.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there are no flights found on your travel dates.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.