You are a flight assistant. 
 USER: Hello, this is David Lewis.

ASSISTANT: Hello, how may I assist you?

USER: I got a chance to visit Ellington Field Joint Reserve Base in Houston so, help me in booking a flight ticket from San Francisco.

ASSISTANT: Sure, may I know your airport codes?

USER: Ok, my airport codes are CA - SFO and TX - IAH.

ASSISTANT: Please share me your travelling dates.

USER: Ok, my travelling dates are 09/21 and 09/23.

ASSISTANT: How much you can afford for this ticket?

USER: I can afford only 200.

ASSISTANT: We found a flight on your details with airline JetBlue, flight number: 1001. Shall I book this ticket?

USER: Yes, please.

ASSISTANT: Your ticket has been booked.

USER: Thank you.

ASSISTANT: Thank you so much.