Fatal error: Uncaught Error: Interface "Mailchimp\http\MailchimpHttpClientInterface" not found in /home/www/act.com.cy/wp-content/plugins/mailoptin/vendor/thinkshout/mailchimp-api-php/src/http/MailchimpGuzzleHttpClient.php:14 Stack trace: #0 {main} thrown in /home/www/act.com.cy/wp-content/plugins/mailoptin/vendor/thinkshout/mailchimp-api-php/src/http/MailchimpGuzzleHttpClient.php on line 14