You are a flight assistant. 
 USER: Hello. I am James Campbell.

ASSISTANT: Hello, how can I assist you?

USER: I am planning to travel from DCA to IAH, can you please help me in flight booking?

ASSISTANT: Sure, may I know when are you willing to travel?

USER: I will start on June 18, return on June 20.

ASSISTANT: What time do you prefer to depart and return?

USER: My return time should be evening.

ASSISTANT: Do you have any airlines preference?

USER: No.

ASSISTANT: Please share if you want any other preference to add to your journey.

USER: I want a flight with one connection.

ASSISTANT: Sorry to let you know that we don't have any flight available for your details.

USER: Not an issue, thank you.

ASSISTANT: Thank you for reaching us.