Critical error on website

Hi, after updating the plugin to the version 2.134.2, everytime I navigate to my website, it return a critical error.

The error log says this:

Un errore di E_ERROR è stato causato nella linea 258 del file xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/HTTP/Request.php. Messaggio di errore: Uncaught Error: Call to undefined function CleantalkSP\Common\HTTP\curl_multi_exec() in xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/HTTP/Request.php:258
Stack trace:
#0 / xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/HTTP/Request.php(194): CleantalkSP\Common\HTTP\Request->requestMulti()
#1 xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/Frontend.php(254): CleantalkSP\Common\HTTP\Request->request()
#2 xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/Frontend.php(86): CleantalkSP\SpbctWP\Scanner\Frontend->getContent()
#3 xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/ScannerQueue.php(2007): CleantalkSP\SpbctWP\Scanner\Frontend->__construct()
#4 xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/SpbctWP/Scanner/ScannerQueue.php(200): CleantalkSP\SpbctWP\Scanner\ScannerQueue->frontend_analysis()
#5 xxxxx/wp-content/plugins/security-malware-firewall/inc/spbc-scanner.php(57): CleantalkSP\SpbctWP\Scanner\ScannerQueue::controllerBackground()
#6 [internal function]: spbc_scanner__controller()
#7 xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Cron.php(121): call_user_func()
#8 xxxxx/wp-content/plugins/security-malware-firewall/lib/CleantalkSP/Common/Cron.php(54): CleantalkSP\Common\Cron->runTasks()
#9 xxxxx/wp-content/plugins/security-malware-firewall/security-malware-firewall.php(342): CleantalkSP\Common\Cron->execute()
#10 / xxxxx/wp-settings.php(517): include_once(‘…’)
#11 xxxxx/wp-config.php(103): require_once(‘…’)
#12 xxxxx/wp-load.php(50): require_once(‘…’)
#13 / xxxxx/wp-login.php(12): require(‘…’)
#14 {main}

I have:

WordPress 6.5.4
Security by CleanTalk (version 2.134.2)
PHP 8.1.27

What can I do?

Thank you.

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