You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I need to reserve a ticket from PHL to OAK, can you help me in doing that?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: My trip dates are Apr 19 to 21.

ASSISTANT: Ok, could I have your name please?

USER: I need a single connecting flight.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: Yes, as I mentioned earlier I need a connecting flight and my name is Alexander Brown.

ASSISTANT: Ok, do you have any other specifications?

USER: Please ensure that my return time must be in evening.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

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

ASSISTANT: You are welcome, have a great day.