This is a feature that the iThemes needs to add but in the meantime if you’re in a pinch you can manually clear the log by deleting rows from the database table titled
“??_itsec_log”. I have already tried and successfully cleared my log using this method.
Log into your hosting CPanel and open “PHPMyAdmin” usually located in the “Databases” section of the CPanel. Once you’ve opened PHPMyAdmin, on the left, navigate to the database for your wordpress installation and select the table
“??_itsec_log”. Each log entry is one row on the table. Click the checkbox next to the entries you want to delete and click “delete”.
Notes:
1. Backup your database first so you can restore it if something goes wrong.
2. Different hosting companies may have different database management tools.
3. If you’re not sure which database belongs to your wordpress installation open up your wp-config.php file located in the root folder of your website and look around line 20-25.