For WordPress there are some plugins to secure adsense account but what about blogger how to protect it from invalid clicks?
Even in WordPress, some available plugins rarely work due to cache issue.
What you can do?
- Use Site Authorization feature
- Use Google AdSense app or toolbar to monitor clicks
- Report https://support.google.com/adsense/contact/invalid_clicks_contact
what to do if we find unusual activity??
In short we can simply monitor nothing else we can do??
Temporarily you can disable showing ad units.
I recieved a barage of Clicks few months back and I simply reported it to Google, the click got removed in few hours. This is the best way to fight against invalid clicks. Dont use Plugins as Gulshan already mentioned the problem with them.