New provider - online game no longer possible?

Since we have a new provider online play is no longer possible. Before was the connection over the telephone jack and now the connection is over the socket of the cable television but surfing the Internet is easily possible.

Previously I have played the following games without any problems: Garry's mod, Rocket League, War Robots, Team Fortress 2, us.w

For Garry's mod, Rocket League, … It says: 'Unable to connect to the server' or the error message: 'Server Connection Timeout'

However, it shows in War Robots, Team Fortress 2, … No error message, but it just loads the whole time but nothing happens.

Here's an example from Rocket Leaue:

Technical specifications:

To my laptop:

Operating system: Windows 7

I have a Thinkpad T430 from Lenovo

To the modem:

Technicolor

Model: TC7200.20

I have the latest drivers installed so it can't be.

I have restarted the router several times, but unfortunately without success. I also contacted the provider, but so far I have not been able to help.

Did anyone have such a problem with you? Does anyone have any advice for me, what else can I do?

Enable the following ports in the router: TCP: 80, 443 & UDP: 7000-9000.

Under Windows, it can be helpful to enter the command "ipconfig / renew" in the "Command Prompt" and confirm with [Enter].

Old and new, do not always fit together.

I suspect that here IPv4 only works on DS-Lite. This means that you share an IPv4 address with other vendors of your vendor, and therefore no port forwarding works.

If that's the case then you can't do anything until the vendors have switched to IPv6.

TCP: 80, 443 is enabled but I do not know how to use UDP. 7000-9000