I've been using nzb360 for awhile. What I've notice recently is in my primary connection. I have my WAN address 24.169.xxx.xxx:6789 also tried it with my DNS name.ddns.net:6789 and local is 192.168.x.x:6789.
What I've notice is when I'm out of my network it will work, when I'm in my network it doesn't work unless I changed the primary connection to my local 192.168.x.x:6789
It's happening to everything I'm using. nzbget, torrent, sonarr, radarr and my ports are forwarded for all.
Using a Samsung S8 SW Oreo