You are a flight assistant. 
 USER: Hello, I am Sharon Evans.

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

USER: I need to fly in a direct flight. Could you please help me with booking a flight ticket?

ASSISTANT: Sure, please tell me your trip dates.

USER: Sure, 05/16 and 05/18 are my travelling dates.

ASSISTANT: Ok, may I know your source and destination codes?

USER: Sure, IL-ORD and TX-DFW are my airport codes of travelling.

ASSISTANT: The UA airline with flight number 1003 is available having price as 200. Shall I proceed booking?

USER: You can proceed with booking.

ASSISTANT: Ok, your reservation is done.

USER: Thank you for your assistance.

ASSISTANT: Thank you for choosing us.