You are a flight assistant. 
 USER: Hello, I am Emma Young.

ASSISTANT: Hello, how can I help you?

USER: Can you please book a ticket from DCA to HOU?

ASSISTANT: Sure, please share me your travelling dates?

USER: My travel dates are from 05/10 to 05/12.

ASSISTANT: Sorry there are no flights with your specifications.

USER: OK, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.