You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Nancy Allen here. I want to travel from San Francisco to Houston for attending a seminar. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My departure date is 05/03 and return date is 05/05.

ASSISTANT: Can I know your airport codes too?

USER: My airport codes are from SFO to IAH.

ASSISTANT: Ok, please wait for a while.

USER: Ok, I will wait. Make sure my connections limit is 1.

ASSISTANT: Sorry, there are no flights found in our database.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us.