forward_station_server_fss/api/v1/Customers/Delete.php

<?php 
  require "connectionDb.php";

if (isset($_POST['delete']) && !empty($_POST['deleteid']) ){

$id = $_POST['deleteid'];

$del = "DELETE FROM customer WHERE id='$id'";

$db->exec($del);

     echo '<script>window.location.href="customers.php"</script>';
}

 ?>
 <style type="text/css">
 	.deleteForm {
 		display: none;
 	}
 </style>
<div class="container deleteForm" id="deleteForm">
	<form action="" method="post">
 	<input type="number" name="deleteid" id="deleteid">
 	<input type="submit" name="delete" value="OK" class="btn btn-danger">
 	</form>
</div>