Duplicate Data Inner Join 3 Tables on PHP MySqli

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PHP

I have duplicate problem when showing data with 3 different table in php with mysqli ext procedural style. My tables are:

kategori: id_kat, nama_kat

subkategori: id_sub, id_kat, nama_sub

supersubkategori: id_supersub, id_sub, id_kat, nama_supersub, kategori_seo

This is my code:

<?php
    require "../config.php";
    $sql = "SELECT * FROM supersubkategori INNER JOIN kategori ON kategori.id_kat = supersubkategori.id_kat
                        INNER JOIN subkategori ON subkategori.id_kat = supersubkategori.id_kat ORDER BY id_supersub ASC";
    $result = mysqli_query($conn, $sql);
    if (mysqli_num_rows($result) > 0)
    {
        while ($data = mysqli_fetch_array($result))
        {
            echo "<tr class=\"table table-striped\">
                            <td align=\"left\">".$data['id_supersub']."</td>
                            <td align=\"left\">".$data['nama_supersub']."</td>
                            <td align=\"left\">".$data['nama_kat']."</td>
                            <td align=\"left\">".$data['nama_sub']."</td>
                            <td align=\"left\">
                                <a href=\"supersub_ubah.php?id_supersub=$data[id_supersub]\">Edit</a>
                                <a href=\"supersub_hapus.php?id_supersub=$data[id_supersub]\">Hapus</a>
                            </td>
                        </tr>";
        }
    }
        else
        {
            echo "Belum ada data.";
        }
    ?>