Upnp problem

[berilliy11]

Hello. I tried to post there few days ago but for some reason i couldn't. I have ppsspp on iPhone 12 pro and i have upnp on my router (ppsspp for pc is working perfectly). My issue:
When im trying to play online with friends through the servers, i need to turn on upnp option, but as soon as i do it, i keep getting messages that upnp device is not found even though i play with the same network as pc. I tried everything: turn on and off upnp on router, restart everything, reinstall ppsspp etc. Funny thing that i actually already played with the same devices few months ago and now i have this issue. Also my router has ping triggering feature and dmz, maybe i should go with them instead, and if so, how can i properly set up them. Thanks for your answers.