Php checkboxes to rows

I need to insert each checkbox to row in MySql.

At the moment i am able to catch only one Checkbox, but i usaly have them 1 - ... who knows how many..

All my checkboxes come from Db like that :

<input type="checkbox" name="lisateenus[]" value="<?php echo $row["id"]; ?>">

On insert it should take the "page id" what is created and after that insert checkbox values to table.

it gets all needed ID-s but it inserts only one checkbox what is checked..

         $result = mysqli_query($con,$query);
    if($result) {
            $last_id = $con->insert_id;
            $error = "Uus Teenus lisatud! ". $last_id;


            $checkBox = implode(',', $_REQUEST['lisateenus']);
            $query="INSERT INTO lisateenuse_seos (p_id, l_id, lisaja) VALUES ($last_id,'" . $checkBox . "','1')";     
            mysqli_query($con, $query) or die (mysql_error() );
            echo "Complete";


        } else {
            $error = "Teenuse lisamine ei õnnestunud";}

So everything is working exept that it only inserts one row, but 3 rows are checked and should be inserted..