Passster conflict

hey,
I have a conflict between Passster and WEB Directory Free.

In WEB Directory, the detail pages are no longer displayed correctly with the following error code:

Fatal error: Uncaught TypeError: passster\PS_Public::filter_the_content(): Argument #1 ($content) must be of type string, null given, called in /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/class-wp-hook.php on line 308 and defined in /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-content/plugins/content-protector/src/class-ps-public.php:185 Stack trace: #0 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/class-wp-hook.php(308): passster\PS_Public->filter_the_content(NULL) #1 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/plugin.php(205): WP_Hook->apply_filters(NULL, Array) #2 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/post-template.php(255): apply_filters(‘the_content’, ‘<div id=”diyweb…’) #3 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-content/themes/enfold/includes/loop-page.php(34): the_content(‘Weiterlesen<spa…’) #4 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/template.php(785): require(‘/homepages/39/d…’) #5 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/template.php(718): load_template(‘/homepages/39/d…’, false, Array) #6 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/general-template.php(204): locate_template(Array, true, false, Array) #7 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-content/themes/enfold/page.php(35): get_template_part(‘includes/loop’, ‘page’) #8 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-includes/template-loader.php(106): include(‘/homepages/39/d…’) #9 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-blog-header.php(19): require_once(‘/homepages/39/d…’) #10 /homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/index.php(17): require(‘/homepages/39/d…’) #11 {main} thrown in?/homepages/39/d905605721/htdocs/clickandbuilds/KruterpdagogenBadenWrttemberg/wp-content/plugins/content-protector/src/class-ps-public.php?on line?185

If I deactivate Passster it works again. However, I would like to continue working with Passster.

Does somebody has any idea?

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