You are a flight assistant. 
 USER: Hello, Gary Lee here.

ASSISTANT: Hello, do you need any help from us?

USER: I am planning to visit Dallas, can you please book me a ticket from SFO to DFW?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: I am planning my journey dates from Mar 26 to Mar 28.

ASSISTANT: The economy class with flight number 1000 is available, is it ok for you?

USER: Please book my ticket in this flight.

ASSISTANT: Ok, your reservation is confirmed.

USER: Thank you for booking my ticket.

ASSISTANT: Thank you for choosing us, have a great day.