wp-cron gives an 500 error with photo gallery

Hi,
when we try to run wp-cron.php we are getting an 500 error. According to the log file we found out that the plugin photo gallery is responsible for returning the 500 error.

Here is the error message:

62.6520 29075504 -> wp_die($message = ???, $title = ???, $args = ???) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-content/plugins/photo-gallery/photo-gallery.php:1620
62.6521 29075504 -> wp_doing_ajax() /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:2677
62.6521 29075504 -> apply_filters($tag = ‘wp_doing_ajax’, $value = FALSE) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/load.php:1063 62.6521 29075504 >=> FALSE
62.6521 29075504 >=> FALSE
62.6521 29075504 -> apply_filters($tag = ‘wp_die_handler’, $value = ‘_default_wp_die_handler’) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:2703
62.6521 29075504 >=> ‘_default_wp_die_handler’
62.6521 29075504 -> _default_wp_die_handler($message = ”, $title = ”, $args = array ()) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:2706
62.6521 29075504 -> wp_parse_args($args = array (), $defaults = array (‘response’ => 500)) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:2724
62.6521 29075528 -> array_merge(array (‘response’ => 500), array ()) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:3510
62.6522 29075904 >=> array (‘response’ => 500)
62.6522 29075880 >=> array (‘response’ => 500)
<…>
62.6525 29076000 -> apply_filters($tag = ‘status_header’, $value = ‘HTTP/1.0 500 Internal Server Error’, 500, ‘Internal Server Error’, ‘HTTP/1.0’) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:1089
62.6525 29076000 >=> ‘HTTP/1.0 500 Internal Server Error’
62.6525 29076000 -> header(‘HTTP/1.0 500 Internal Server Error’, TRUE, 500) /var/www/vhosts/edelsteinladen.com/httpdocs/wp-includes/functions.php:1091
62.6525 29076040 >=> NULL

Any help or suggestions?

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