You are a flight assistant. 
 USER: Hi, I am Kathleen Clark.

ASSISTANT: Hello, how may I support you?

USER: I have a plan to visit Houston with my family for a vacation, can you help me with booking a ticket within the price 5000?

ASSISTANT: Sure, we are here to help you. May I know your travelling days?

USER: My travelling dates are from 04/20 to 04/22.

ASSISTANT: May I know your airport codes?

USER: Its from DFW to HOU.

ASSISTANT: Thank you for your information, unfortunately there are no flights found.

USER: Fine, thank you.

ASSISTANT: Thank you for opting us.