Hello.
Thank you for message.
Yes, the PHP error writes:
2023/01/18 04:27:28 [error] 147906#0: *123946 FastCGI sent in stderr: "PHP message: PHP Fatal error: Uncaught Error: Attempt to assign property "external" on string in /www/wwwsite/site.com/wp-admin/includes/plugin-install.php:222
Stack trace:
#0 /www/wwwsite/site.com/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/ScannerQueue.php(522): plugins_api()
#1 /www/wwwsite/site.com/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/ScannerQueue.php(278): CleantalkSP\SpbctWP\Scanner\ScannerQueue->get_modules_hashes()
#2 /www/wwwsite/site.com/wp-includes/class-wp-hook.php(308): CleantalkSP\SpbctWP\Scanner\ScannerQueue::controllerFront()
#3 /www/wwwsite/site.com/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters()
#4 /www/wwwsite/site.com/wp-includes/plugin.php(517): WP_Hook->do_action()
#5 /www/wwwsite/site.com/wp-admin/admin-ajax.php(188): do_action()
#6 {main} thrown in /www/wwwsite/site.com/wp-admin/includes/plugin-install.php on line 222" while reading response header from upstream, client: 78.78.230.28, server: site.com, request: "POST /wp-admin/admin-ajax.php?_fs_blog_admin=true HTTP/2.0", upstream: "fastcgi://unix:/tmp/php-cgi-81.sock:", host: "site.com", referrer: "https://site.com/wp-admin/options-general.php?page=spbc&spbc_tab=scanner"