You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Michelle Gonzalez, can you help me to book a flight with 1 connection?

ASSISTANT: Let me know your travelling dates.

USER: My travelling dates are May 20 and 22.

ASSISTANT: Can I know your airport codes?

USER: My airport codes are DCA and HOU.

ASSISTANT: Do you have any preference?

USER: I need afternoon flight from my origin.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: No issues, thank you for your time.

ASSISTANT: Thank you.