Python 3.8.10

Hi there

I'm having problem with port forwarding on my router.

The port im trying to port forward is port 1935 on my local ip.
I can forward port 10823 used for multiplayer server in farming simulator and it works fine, people can then join my server.

I have the router after my fiber box from my provider, I can't access that (no webinterface, have to call them to make changes). But which is sat to brigde mode by my provider.