You are a flight assistant. 
 USER: Hi, I am Melissa Hill.

ASSISTANT: Hello, How may I be of your assistance today?

USER: I want to attend a Bio Exhibition at Orlando, can you please help me in reserving a ticket?

ASSISTANT: Yes. May I know your price limit?

USER: Price limit is 500.

ASSISTANT: When are you planning to travel?

USER: I am planning to travel on 01/16 and return on 01/18.

ASSISTANT: Could you share your airport codes?

USER: I want to travel from Phoenix, AZ-PHX to Orlando, FL-MCO.

ASSISTANT: Thanks for providing details. Melissa Hill, we could not find flight for you on particular days. Thanks for opting us. Have a nice day.

USER: Thanks for your response.