You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,. How can I help you?

USER: I am Elizabeth Brown. I have a plan to visit the Chabot space and science center with my college friends in Oakland from Dallas to attend the comic con exhibition. Would you please help me for booking a ticket?

ASSISTANT: Sure, we are here to assist you. How much you can efford for a flight ticket?

USER: Price limit should be below 5000.

ASSISTANT: Help me with the source and destination codes.

USER: My source code is TX-DFW and destination code is CA-OAK.

ASSISTANT: May I know your planned dates of travelling?

USER: My planned dates are 06/03 and 06/05.

ASSISTANT: Thanks for providing the details. Please wait for a minute, I will revert you with the availability.

USER: Ok.

ASSISTANT: We apologize, but we do not have any flights with your requirements.

USER: OK, no issue at all. Thank you for your information.

ASSISTANT: Thank you for opting our service.