diff --git a/submit.php b/submit.php
index 1109af8..f6f3940 100644
--- a/submit.php
+++ b/submit.php
@@ -1,7 +1,9 @@
 <?php
 session_start();
 
-$CONVERT_CMD = "/usr/bin/pdftk";
+require "config.php";
+
+#$CONVERT_CMD = "/usr/bin/pdftk";
 
 require_once('TCPDF/tcpdf.php');
 
@@ -199,6 +201,11 @@ function convert($row) {
 
 function calcSum(){
 	$sum =0;
+	if (!isset($_POST['amount'])) {
+		echo "wrong parameters";
+		die;
+	}
+
 	foreach ($_POST['amount'] as $val){
 		var_dump($val);
 		$sum += floatval(str_replace(",",".",$val));