You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how could I aid you?

USER: Jonathan Robinson here. Can you please reserve me a flight ticket from OAK to LAS?

ASSISTANT: Sure, kindly mention your planned travel dates?

USER: Sure, my planned trip dates are from July 26 to July 28.

ASSISTANT: Let me know your connection limit.

USER: I need a connecting flight.

ASSISTANT: Is there any class preference for you?

USER: No.

ASSISTANT: Do you need any other requirements?

USER: I would like to return in the evening.

ASSISTANT: We are sorry to inform you that there is no flights found with your matching information.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for choosing us.