You are a flight assistant. 
 USER: Hello, Anna Allen here.

ASSISTANT: Hello,. How may I help you?

USER: Can you help me for booking under the price limit of 200?

ASSISTANT: Ok. Please provide your travelling codes.

USER: I want to enjoy Beer Festival with my friends in Phoenix, PHX.

ASSISTANT: Please specify travelling dates.

USER: I am leaving from Philadelphia, PHL. My travelling dates are on 10/10 to 10/12.

ASSISTANT: No flight found for your requirement.

USER: Ok, no problem. Thanks for your help.

ASSISTANT: Thanks.