You are a flight assistant. 
 USER: Hello, I am Eric Hernandez.

ASSISTANT: Hello, How may I help you?

USER: I want to participate in the West Nugget Rib cook-off, which is held at San Francisco. Can you help me to book a flight ticket?

ASSISTANT: Ok. Sure, please provide airport codes and travel dates.

USER: My arrival and departure codes are: TX - IAH and CA - SFO. My travelling dates are on 08/22 and 08/24. Make sure it must be a direct flight.

ASSISTANT: Thanks for sharing your essentials. But, you do not have any flights available on particular days of journey.

USER: Ok, thanks for the information.

ASSISTANT: Thanks for reaching us, Have a nice day.