You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I serve you?

USER: I am Amy Rodriguez, can you help me to book a flight within 500 price limit?

ASSISTANT: Yes, please I will help you with flight ticket booking. May I know your travel dates please?

USER: My travelling dates are 03/17 and 03/19.

ASSISTANT: Now please tell me your airport codes?

USER: My airport codes are LAX and IAH.

ASSISTANT: Thanks for your waiting patiently. But I am sorry to say that there are no flights available.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you.