Since a few updates I have mostly laggs (I'm being ported back / opponent runs on the spot / can't build), mostly when I'm in a fight with other opponents. I have a 400K line with 20 ping and a sufficiently good PC. It's only been a while since it lay there.
It's not fun to play like that. Hopefully someone knows the solution.
The server or your opponents may have connection problems.
Sounds more like an internet problem. However, I would update your drivers from the graphics card. That also helped extremely at MW. If you have an Nvidia card, I recommend Geforce Experience. This is a good and official program which searches for and installs the appropriate driver. You can also use it to do other things. Can you take a look at it?
As far as I know, Fortnite doesn't support IPv6, I don't think you have a public IPv4 address.
It only helps to use your smartphone as a hotspot or to go to a provider with IPv4.
If you have a Telekom mobile phone contract, you can also try a "Telekom Fon" hotspot.
