I have a 2018 Mac mini that I bought last August and I never had a problem with it. About a week or two ago I started having a problem where my WiFi stays on but I suddenly loose the internet conection, other computer and devices in the network work just fine and usually turning the Wi-Fi off and on again works, but after a while it happens again and I have tried everything to my knowledge to no avail. I have tried renewing DHCP lease, changing the MTU, deleting network .plist files to restart the preferences, creating a new location, forgeting the network and adding it again, restarting my router and creating a new network, changing the DNS, restarting PRAM and SMC and reinstalling macos.
I realize a silver bullet fix might not be easily recommended, so what kind of process or guide would help diagnose the problem?