Not loading certain websites (ipv4 router adress not found?)

Hello everyone,

I have a problem since a few days that i cannot resolve myself.

I use a macbook air running Catalina 10.15.7 connected to my home network Vodafone kabel station.

I have connection and I can load websites such as Google, Gmail, Facebook, Wikipedia, Youtube.

On the other had I cannot load most of the other website, including Vodafone, Amazon and eBay, newspapers websites, smaller sites etc.

It says I cannot establish connection to the server.

I've tried connecting other devices (phone, apple devices, pc) to my Vodafone station and they work perfectly, they load all pages.

I've tried as well to connect my macbook to other wifi networks, and it also works perfectly!

So the problem seems to appear when i connect my macbook to my home network, which is the one i really need, I'm in home working for the next 5 months at least.

I've done some researches and seems like i cannot reach ipv4 address, while i connect to ipv6 addresses (google, etc.).

I followed tutorials, reset factory configurations, manual configurations, but nothing seems to work.

Something that i noticed, comparing my setting to other devices, is that in ipv4 configurations, i don't have an router's IP address, and i cannot insert it manually, it doesn't recognize it…

I would be very grateful is someone has an idea about how I could fix this.

Thank you very much!