Php warning with web monitoring tool

We use a web monitoring tool (https://www.port-monitor.com/) but it generates a lot of warn in our apache log. Nothing too worrying but it make our logs a bit messy

We use OJS 3.1.2.4

Logs :

[Fri Jul 03 05:39:15.748118 2020] [php7:warn] [pid 17594] [client 37.187.141.25:54286] PHP Warning: count(): Parameter must be an array or an object that implements Countable in /var/www/html/ojs/cache/t_compile/65bfc3e024c2e9104f46e23b73376a9455e3df0e^51cfb9321c891ada9323e7942962579e7e4324d1_0.app.frontendpagesindexSite.tp.php on line 46, referer: https://www.port-monitor.com

The referenced line contains :

<?php if (!count($_smarty_tpl->tpl_vars['journals']->value)) {?>

Any idea to clear this ?