我怎么能记住输入中的文字

Question

I have two problems with the following code, i.e.

1. I would like saved values in input to be remembered, because now it returns the value "
   Notice : Undefined variable: name_check in".

2. If the domain length is shorter than 5 characters, it returns an error but only at the first input, and I would like the validation error to be at each of the inputs.

<?php
    require_once "connect.php";

    $connect = @new mysqli($host, $db_user, $db_password, $db_name);

    if(isset($_POST['send'])) 
    {
        $all_ok=true;
        $id = $_POST['id']; 
        $domain_name = $_POST['domain_name']; 
        foreach ($domain_name as $value) 
        {
            if (strlen($value)<5)
            {   

                $all_ok=false;
                $_SESSION['e_name']="Wpisana domena jest zbyt króka.";
            }
        }
        $_SESSION['fr_name'] = $value;

        if ($all_ok==true)
        {
            $count = count($id); 
            for($i=0;$i<$count;$i++) {

                $connect->query('UPDATE domains SET domain_name="'.$domain_name[$i].'" WHERE id='.(int)$id[$i].'');
            }
            $_SESSION['well_done']=true;
            echo "udana walidacja";
        }
    }
    ?>
    <style>
            .error
            {
                color:#cc0000;
                margin-top: 5px;
                margin-bottom: -5px;
                font-size:12px;
            }

        </style>
    <form method="POST" action="">
    <table>
    <?php
    $result = $connect->query("SELECT * FROM domains");

        $how_nick = $result->num_rows;

        if ($how_nick != 0) {

           while($data = $result->fetch_assoc())
          {
    ?>  
    <tr>
        <td>Nazwa Domeny:<br> <input type="text" value="<?php
                if (isset($_SESSION['fr_name']))
                {
                    echo $_SESSION['fr_name'];
                    unset($_SESSION['fr_name']);
                }
                else
                {
                    echo $data['domain_name']; 
                }   
            ?>" name="domain_name[]"><br /><?php
                if (isset($_SESSION['e_name']))
                {
                    echo '<div class="error">'.$_SESSION['e_name'].'</div>';
                    unset($_SESSION['e_name']);
                }
            ?></td>
        <td><input type="hidden" name="id[]" value="<?php echo $data['id'];?>"/></td>
    </tr>
    <?php            
    }}
    ?>         
    </table>
    <br /><center><input class="button" type="submit" name="send" value="Zapisz"></center>
    </form>