This is not a normal 'no internet connection' problem

Hi,

I got stuck with this issue for a couple of days and need sone help from more advance users.

I've upgraded to Catalina a week ago and all was well until a few days back my IMac lost connection to the internet after waking it up in the morning....

My internet and router are fine. Other devices (mac book and iphone) work fine - either on wifi or ethernet. Non apple devices work fine on ethernet connection.

My imac shows that is connected to the wifi or/and to the ethernet but non of the apps/software can connect (speedtest, Spotify, Safari ect).

I've tried reseting the router, changing cables, running imac in safe mode, reinstalling Catalina.....

nothing works.....

Strange thing is that it was all fine used on a daly basis even after installing Catalina it was all good.

I simply run out of ideas.

Can anyone help with next steps?

Much appreciate your help.

Cheers