From the FAQ:
How come I still see visitors being blocked from other security plugins?
Other wordpress plugins handle the visitors also. They might run before iQ Block Country or they might run after iQ Block Country runs.
This however does not mean this plugin does not work, it just means somebody tried to access a certain page, post or your backend and another plugin also handled the request.
If you are worried this plugin does not work you could try to block your own country or your own ip address and afterwards visit your frontend website and see if it actually works. Also if you have access to the logfiles of the webserver that hosts your website you can see that these visitors are actually denied with a HTTP error 403.
This plugin does not work, I blocked a country and still see visitors!
Well, this plugin does in fact work but is limited to the data MaxMind provides. Also in your statistics software or logfiles you probably will see log entries from countries that you have blocked. See the “How come I still see visitors…” FAQ for that.
If you think you have a visitor from a country you have blocked lookup that specific IP address on the tools tab and see which country MaxMind thinks it is. If this is not the same country you may wish to block the country that MaxMind thinks it is.