You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you?

USER: I want to reserve my ticket from DFW to PHL to visit Philadelphia, can you please help me in booking?

ASSISTANT: Sure, please share you planned travel dates.

USER: Sure, my planned dates of journey are from Apr, 16 to Apr, 18.

ASSISTANT: Do you prefer either economy or business class?

USER: Not required.

ASSISTANT: Please let me know if you have any other preference.

USER: Not required.

ASSISTANT: May I know your name please?

USER: Sure, my name is Robert Taylor.

ASSISTANT: We done't have any flight available on given dates from you.

USER: Ok, no problem. Anyways, thank you for your service.

ASSISTANT: Thank you.