Reduc throws errors

I use the Vorosa theme template for cloud-aviation.de and when I try to update to Version 4.3.26 I receive errors:

Deprecated: Die Funktion Redux::setHelpTab ist seit Version Redux 4.3 veraltet! Verwende stattdessen Redux::set_help_tab( $opt_name, $tab ). in /www/htdocs/w018b665/cloud-aviation.de/wp-includes/functions.php on line 5383

Deprecated: Die Funktion Redux::setHelpSidebar ist seit Version Redux 4.3 veraltet! Verwende stattdessen Redux::set_help_sidebar( $opt_name, $content ). in /www/htdocs/w018b665/cloud-aviation.de/wp-includes/functions.php on line 5383

Warning: Cannot modify header information – headers already sent by (output started at /www/htdocs/w018b665/cloud-aviation.de/wp-includes/functions.php:5383) in /www/htdocs/w018b665/cloud-aviation.de/wp-admin/includes/misc.php on line 1416

Warning: Cannot modify header information – headers already sent by (output started at /www/htdocs/w018b665/cloud-aviation.de/wp-includes/functions.php:5383) in /www/htdocs/w018b665/cloud-aviation.de/wp-includes/functions.php on line 6865

Warning: Cannot modify header information – headers already sent by (output started at /www/htdocs/w018b665/cloud-aviation.de/wp-includes/functions.php:5383) in /www/htdocs/w018b665/cloud-aviation.de/wp-admin/includes/template.php on line 2068

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