Clam on access scanning

[Jim]

I wanted to get Clam's on access virus scanner working.   It's running, 
but doesn't block the eicar test virus.  I type cat eicar.com.txt and it 
appears in the terminal.  System activity shows clamd running with my 
username, clamonacc running as root and freshclam running as the user 
clamav.   I have Kubuntu 20.04 installed.  Apparently I'm missing 
something.  Any help will be appreciated.  Thanks