You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I want to book a flight ticket to meet my friends at PA. Can you help me?

ASSISTANT: Sure, I am here to help you for this. Could you please share me your airport codes?

USER: Thank you. Sure, ORD and PHL are my nearest airport codes .

ASSISTANT: When are you planning your trip?

USER: May 10th and 12th are my travelling dates.

ASSISTANT: Is there any other specifications regrading your journey?

USER: No.

ASSISTANT: May I know your name please?

USER: Myself Brain Roberts.

ASSISTANT: Sorry for inconvenience, no flights are found with your requirements.

USER: No issue.

ASSISTANT: Thank you very much for contacting our agency.

USER: Thank you for the information.

ASSISTANT: You are welcome.