You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Jacob Moore, can you help me to book a flight ticket?

ASSISTANT: Sure, please tell your travelling airport codes?

USER: I just want to visit Liberty Bell in PHL from ATL.

ASSISTANT: Ok, please forward me your travelling dates?

USER: My planning dates are 09/20 and 09/22.

ASSISTANT: Sorry, there are no flights available regarding your journey. Do you want any more information please?

USER: Oh! that's really sad. No, thank you.

ASSISTANT: Thank you and have a nice day.