How to fix internet connection in macOS 10.15?

Question

WiFi

Everything is fine, but the Internet works from 1 to 5 seconds after switching Wi-Fi.
This is what the process looks like;
I connect to the network;
Works 2-3 seconds;
Disappears forever (Internet, no connection with the router);
Turn on / off wifi;
Works 2-3 seconds;
Lost access to the Internet, with a router it is.
Nothing is loaded, the connection with the router is normal.
If someone came across, please tell me the solution?

Answer 1

As soon as I installed the operating system, along with it I got some kind of AHAVPN.
As soon as this crap starts - the Internet instantly disappears.
It can be disabled in Network Pereferences -> uncheck "Connect on demand", Press Disconnect -> Apply.
Everything is working smoothly.
I want to note that I did not set it separately, but everything happened immediately after the OS update.