Miniupnpd can't access port forwards from my own lan

Software SW help
1

UPNP port forwards work great for anyone accessing my public ip, but not for myself when coming from my internal lan network. why is that and how can I change it?

Say I use filegive -u -p file.ext

http://external_ip:12345/iwwtmb/file.ext

work fine from my mobile phone LTE connection, but I can’t access it from my LAN.

Thanks!