PHP mail Debian wheezy stopped sending mail overnight

if(!$mail->Send()) {
            echo "Mailer Error: " . $mail->ErrorInfo ."\n";
        } else {
            echo "Message sent!\n";
        }

/var/log/phpmail.log

...
mail() on [/var/www/*/includes/phpmailer/class.phpmailer.php:516]: To: *@*.se -- Headers: Date: Mon, 7 Aug 2017 15:27:03 +0100 Return-Path: *@*.se From: No-reply * <*@*.se> Cc: *@*.se Reply-To: No-reply * <*@*.se> Message-ID: <3d58d154e5561286b3b64bd8900f7a05@*.se> X-Priority: 3 X-Mailer: PHPMailer 5.2.4 (http://code.google.com/a/apache-extras.org/p/phpmailer/) MIME-Version: 1.0 Content-Type: multipart/alternative; 	boundary="b1_3d58d154e5561286b3b64bd8900f7a05"
mail() on [/var/www/*/includes/phpmailer/class.phpmailer.php:516]: To: * <*@*.se>,* <*@gmail.com> -- Headers: Date: Tue, 8 Aug 2017 11:23:29 +0200 Return-Path:*@*.se From: No-reply *<*@*.se> Reply-To: No-reply *<*@*.se> Message-ID: <6906cac567ff5ce0b9fd4a72b1ca7f96@*.se> X-Priority: 3 X-Mailer: PHPMailer 5.2.4 (http://code.google.com/a/apache-extras.org/p/phpmailer/) MIME-Version: 1.0 Content-Type: multipart/mixed; 	boundary="b1_6906cac567ff5ce0b9fd4a72b1ca7f96"
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