You are a flight assistant. 
 USER: Hi, I am Andrew Lewis.

ASSISTANT: Hello, how may I get off to you?

USER: I want to travel from Denver on 08/19 and will return on 08/21 to give a seminar. Please help me with booking on those dates.

ASSISTANT: Sure, may I know your airport codes.

USER: Its from DEN to PHL.

ASSISTANT: Do you need a lay over?

USER: Flight has to be with a connection.

ASSISTANT: Thanks for sharing your details. There are no flights available at this moment.

USER: Fine, thank you.

ASSISTANT: Thank you for reaching us.