PHP help

<?php

$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";


$mysqli = new mysqli($servername, $username, $password, $dbname);

if ($mysqli->connect_error) {
    die("Connection failed: " . $mysqli->connect_error);
}

$earnedpoints = false;
$account = $_POST['name'];
$account = mysql_real_escape_string($account);

if ($account == "") {
    echo 'Enter an account name!';
    exit();
}

$ip = $_SERVER['REMOTE_ADDR'];
$time = time();

$stmt = $mysqli->prepare("SELECT *, SUM(`times`) as amount FROM votingrecords WHERE account='$account' OR ip='$ip'");
$lasttime = mysql_fetch_array($stmt);
$amount = $lasttime['amount'];
$insertnew = false;
if ($amount == "") {
    $insertnew = true;
}
$timecalc = $time - $lasttime['date'];
if (!$insertnew) {
    if ($timecalc < 21600) {
        echo ' Hello '. $account .' you have already voted with this account ('. $account .') or IP ('. $ip .') in the last 6 hours!';
        echo ' Last voted on: '. date('M d\, h:i:s A', $lasttime['date']) .'';
        echo '<html>';
        echo '<head>';
        echo '<meta HTTP-EQUIV="REFRESH" content="10; url=http://www.">';
        echo '</head>';
        echo '<body>';
        echo '<br><br>You will be redirected to the main website in 10 seconds.';
        echo '</body>';
        echo '</html>';
        exit();
    } else {
        $update = $mysqli->prepare("UPDATE votingrecords SET account='$account', date='$time', times=times+1 WHERE ip='$ip'");
            if (!$update) {
                $message  = 'Invalid query: ' . mysql_error() . "\n";
                $message .= 'Whole query: ' . $update;
                die($message);
            } else {
                $earnedpoints = true;
            }
        }
} else {
    $success = $mysqli->prepare("INSERT INTO votingrecords (`account`, `ip`, `date`, `times`) VALUES ('$account', '$ip', '$time', 1)");
    if (!$success) {
            $message  = 'Invalid query: ' . mysql_error() . "\n";
            $message .= 'Whole query: ' . $success;
            die($message);
    } else {
        $earnedpoints = true;
    }
}


if ($earnedpoints) {
    $points = $mysqli->prepare("UPDATE accounts SET votepoints = votepoints + 2 WHERE name='$account'");
    if (!$points) {

            $message  = 'Invalid query: ' . mysql_error() . "\n";
            $message .= 'Whole query: ' . $stmt;
            die($message);
    }
    $stmt->execute();
    $stmt->close();
    echo '<html>';
    echo '<head>';
    echo '<meta HTTP-EQUIV="REFRESH" content="0; url=http://www.gtop100.com/">';
    echo '</head>';
    echo '</html>';
} else {
    echo 'There was an error processing your request.';
    exit();
}
?>