[Defender Pro] Defender causing high usage

The WP Defender app is causing high usage on our server. Here is an example from the log:

[30-Jun-2019 21:56:44 UTC] PHP Warning: count(): Parameter must be an array or an object that implements Countable in /home/britishicehockey/public_html/wp-content/plugins/wp-defender/app/module/ip-lockout/controller/main.php on line 643

Can you advise?