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

ASSISTANT: Hello, how may I help you at this moment?

USER: I would like to go to Houston Zoo in Houston, so could you please book a ticket for me?

ASSISTANT: Can I have your travelling dates?

USER: I would like to go on 04/22 and return back on 04/24.

ASSISTANT: Please let me know your route plan.

USER: My source and destination airport codes are DTW and HOU.

ASSISTANT: Please let me a moment to check the availability.

USER: Ok, ensure it is a single connecting flight.

ASSISTANT: Sorry, there is no connecting flights available on your required dates.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome. Thank you for reaching us.

USER: Welcome.