Reverse DNS not working in my Mac terminal for North Korean website

Hey everyone.
I am playing around with the terminal in my Mac and noticed an issue. If I do a reverse DNS lookup of IP address 175.45.176.69 (see http://reverseip.domaintools.com/search/?q=175.45.176.69), it gives me the host name "airkoryo.com.kp" which is correct.
However, when I do "host 175.45.176.69" or "nslookup 175.45.176.69" or "dig -x 175.45.176.69" in my terminal, none of my typical IP to host name commands work and print out "airkoryo.com.kp". Does anyone know why that is? Is North Korea blocking some of my requests? Am I not running the right terminal command?

Thanks!