You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I serve you?

USER: I am going to conduct the Auto-Show event at Charlotte, CLT.

ASSISTANT: Ok.

USER: Aid me to make a reservation for reaching the destination under the price limit of 500.

ASSISTANT: Sure, I am here to aid you.

USER: Thank you.

ASSISTANT: When you are planning to start your journey?

USER: My journey starts on 04/22 from San Francisco.

ASSISTANT: May I have your take off airport code?

USER: Take of point is San Francisco, SFO.

ASSISTANT: Can you please provide your return date?

USER: Return date is on 04/24.

ASSISTANT: Please, wait a minute.

USER: Ok, I will wait.

ASSISTANT: Thank you for waiting, there are no flights available that matches your requirements.

USER: Fine, thank you for your information.

ASSISTANT: May I know your good name?

USER: Jeffrey Roberts is my name.

ASSISTANT: Thank you for approaching us.