Rev slider came with theme but unable to update. What can I do to solve it ? Thanks in advance.
log error:
AH01071: Got error ‘PHP message: PHP Fatal error: Uncaught Error: operator not supported for strings in /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-content/plugins/revslider/inc_php/framework/base_admin.class.php:73\nStack trace:\n#0 /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-content/plugins/revslider/revslider_admin.php(237): UniteBaseAdminClassRev::addMetaBox(‘Revolution Slid…’, Object(UniteSettingsAdvancedRev), Array, NULL)\n#1 /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-content/plugins/revslider/revslider_admin.php(68): RevSliderAdmin->addSliderMetaBox()\n#2 /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-content/plugins/revslider/revslider_admin.php(40): RevSliderAdmin->init()\n#3 /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-content/plugins/revslider/revslider.php(147): RevSliderAdmin->__construct(’/var/www/vhosts…’)\n#4 /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-settings.php(342): include_once(’/var/www/vhosts…’)\n#5 /var/www/vhosts/maattandtechniek.nl/httpdocs/wp-config.php(80): require_once(’/…\n’, referer: https://www.maattandtechniek.nl/