Compare what your router reports as ip and compare what your public ip is. If its not the same then that means you are behind a nat(?)(or something else) and you can’t port forward now.
You are probably behind a nat. I contacted my isp and they disabled it, since it works perfectly!
I replaced gmail with protonmail and everything else with nextcloud. Couldn’t go back.
Wrong choice buddy (wayland is the best thing ever happened trust me 100%!!!)