You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you today?

USER: I want to book a flight ticket from Philadelphia to attend a client meeting in Dallas, could you please help me to book a flight ticket with single connection?

ASSISTANT: Sure, I will help you with that. Can you please share your preferable journey dates?

USER: Sure, I am planning to start on Apr 1st and my return date will be on Apr 3rd.

ASSISTANT: Can you please provide you source and destination airport codes?

USER: My boarding and landing airport code are PHL and DFW.

ASSISTANT: May I know your name please?

USER: I am Richard Baker.

ASSISTANT: Do you have any connection limit?

USER: I have already mentioned above.

ASSISTANT: Is there any specifications?

USER: No more specifications.

ASSISTANT: I am sorry to say that there is no flight found under your details.

USER: That's ok, I'll choose any alternative to reach my destination. Thank you for your information.

ASSISTANT: Thank you for reaching us.