junk mail blacklist only works part of the time

When I use “Move to junk” and blacklist the email or domain; it only works part of the time.  The same junk stuff keeps coming back.  Some of my junk goes away and the blacklist seems to work. On other stuff it does not.  What am I doing incorrectly?

Hello Paul,
are these messages coming from the same domain? Maybe the same kind of spam comes from different domains?
You can check the blocked domains in the Blacklist rule in Tools>Rules.
Can you also tell me which version of eM Client are you currently running? Check Help>About section for exact number.

Regards,
Olivia