Fatal error – Uncaught TypeError: fclose()

Hi, I hope you’re well.

Your plugin is causing the following error on my website:

Error Details
=============
An error of type E_ERROR was caused in line 59 of the file /wp-content/plugins/forms-for-campaign-monitor/forms/core/Log.php. Error message: Uncaught TypeError: fclose(): Argument #1 ($stream) must be of type resource, bool given in /wp-content/plugins/forms-for-campaign-monitor/forms/core/Log.php:59
Stack trace:
#0 /wp-content/plugins/forms-for-campaign-monitor/forms/core/Log.php(59): fclose(false)
#1 /wp-content/plugins/forms-for-campaign-monitor/forms/core/Log.php(140): forms\core\Log::getFileName()
#2 /wp-content/plugins/forms-for-campaign-monitor/forms/core/Security.php(55): forms\core\Log::write(Array)
#3 /wp-content/plugins/forms-for-campaign-monitor/forms/core/Ajax.php(139): forms\core\Security::verifyCaptcha(NULL, '')
#4 /wp-content/plugins/forms-for-campaign-monitor/forms/core/Ajax.php(33): forms\core\Ajax::ajaxFormHandler()
#5 /wp-content/plugins/forms-for-campaign-monitor/forms/core/Application.php(215): forms\core\Ajax::run()
#6 /wp-content/plugins/forms-for-campaign-monitor/campaign-monitor.php(75): forms\core\Application::run()
#7 /wp-includes/class-wp-hook.php(341): {closure}('')
#8 /wp-includes/class-wp-hook.php(365): WP_Hook->apply_filters(NULL, Array)
#9 /wp-includes/plugin.php(522): WP_Hook->do_action(Array)
#10 /wp-settings.php(593): do_action('plugins_loaded')
#11 /wp-config.php(90): require_once('')
#12 /wp-load.php(50): require_once('')
#13 /wp-admin/admin-post.php(17): require_once('')
#14 {main}
thrown

The error is getting logged every day – could you support me with this issue, please?