如何修复此css我的产品将不会连续显示3

The columns widths are not showing 3 in a row I tried inline, inline-block, flex

I also tried using different cards and forms but nothing seems to work they always display underneath each other I have changed form

to and also changed the headers but they will not get in one line

<?php
include 'includes/header.php';
    include 'includes/conn.php';
?>


<section class="white-section" id="pricing">

<h2 class="section-heading">A Plan for Every Dog's Needs</h2>
<p>Simple and affordable price plans for your and your dog.</p>

<?php
 $query = "SELECT * FROM products ORDER BY prod_id ASC";
 $result = mysqli_query($conn,$query);
if(mysqli_num_rows($result)>0){
while($res = mysqli_fetch_array($result)) {
?>




            <div class="row">

              <div class="pricing-column  col-md- 
                           4">
                <div class="card">
                  <div class="card-header">
                    <h3><?php echo $res['prod_name'];?> 
                                </h3>
                  </div>
                  <div class="card-body">
                    <h2 class="price-text">R<?php echo 
                   $res['prod_price']; ?></h2>
                    <p><?php echo $res['prod_1'];?></p>
                    <p><?php echo $res['prod_2'];?></p>
                    <p><?php echo $res['prod_3'];?></p>
                    <button class="btn btn-lg btn-block 
              btn-outline-dark" type="button">Sign Up</button>
                  </div>
                </div>
              </div>

My code seems to work correctly but with some of the cards/forms it will display one correctly and the rest will get smaller every time it loads a new product

 <?php }}?>
 </section>




 .white-section {
 background-color: #fff;
 }

 #pricing {
 padding: 100px;
  }

 .price-text {
  font-size: 3rem;
  line-height: 1.5;
  }

  .pricing-column {
   padding: 3% 2%;
  }

  h1, h2, h3, h4, h5, h6 {
  font-family: "Montserrat-Bold";
  display: inline-grid;
  }

  p {
  color: #8f8f8f;
  display: inline-grid;
  }