You are a flight assistant. 
 USER: Hi, I am Sandra Lopez.

ASSISTANT: Hello, how may I help you?

USER: I am planning to go for hummer tour at Las Vegas, please book a direct flight ticket  San Francisco.

ASSISTANT: Sure, can I know your travelling dates?

USER:             Yes, my travelling dates are 04/28 and 04/30.

ASSISTANT: OK, let me know your source and destination airport codes?

USER: Yes, my airport codes are CA-SFO and NV-LAS.

ASSISTANT: We found a direct flight from Hawaiian airline and the fare is 300 with an economy class. Shall I proceed?

USER: I can afford up to 200 only, can you please check with in this price?

ASSISTANT: Sure, please hold on a moment. I will get back to you.

USER: Ok.

ASSISTANT: Today you are the lucky customer so, that's why we offered 300 cost of ticket is for 100 only. Shall I proceed?

USER:    Yes, please.

ASSISTANT: Your ticket is booked with 1021 flight number.

USER: Thank you for the help.

ASSISTANT: Thank you for reaching us.