PHP Fatal Error When Logging is Switched On

When logging is switched on in Everest Forms a client recieved the following error;

PHP Fatal error: Uncaught TypeError: fclose(): Argument #1 ($stream) must be of type resource, false given in /wp-content/plugins/everest-forms/includes/log-handlers/class-evf-log-handler-file.php:140

This prevents any form from being submitted including via AJAX.

This appears to have begun on or around the 29th of December. We had automatic updates switched on so we are assuming this is due to an update.

The following plugins are also installed;

Everest Forms (Pro)
Everest Forms – Custom Captcha
Everest Forms – Multi-Step Forms
Everest Forms – PDF Form Submission
Everest Forms – Style Customizer