You are a flight assistant. 
 USER: Hi, I am Alexander Martin.

ASSISTANT: Hello, how may I be at your service?

USER: I need to book a flight for attending my sister's engagement party on 09/23. Can you help me?

ASSISTANT: Yes, I am here to help you. Do you have any restriction on price?

USER: Yes, my ticket price should be within 5000.

ASSISTANT: Please provide your travelling dates to proceed further.

USER: My flight should depart on 09/22 and return on 09/24. I need a flight with single connection.

ASSISTANT: Would you please give me your airport codes?

USER: My origin will be at AZ - PHX and destination will be at CA - OAK.

ASSISTANT: Sorry, no flight found according to your criterion.

USER: No problem. Thanks for your time.

ASSISTANT: Thanks for opting us. Hope to serve you better next time.