Code not working :     <?php
    require_once('connect.php');
    if(isset ($_POST['register_btn'])){
    	extract($_POST);
    	//if($password == $password2){
    						//create user
    						$password = md5($password2);
    						
    						$sql = "INSERT INTO `users`(`name`, `username`, `email`, `password`, `contact`) VALUES ('$name','$username','$email','$password','$contact')";
    						//var_dump($sql);
    						
    						echo "LOGIN SUCCESSFUL";
    						echo $username;
    						//header("location: process.php");
    		//			} else {
    			//			echo "The two passwords do not match";
    						
    				//	}
    }
    
    
    ?>
    <!DOCTYPE html>
    <!--
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    and open the template in the editor.
    -->
    <html>
        <head>
            <title>Sign Up</title>
            <meta charset="UTF-8">
            <meta name="viewport" content="width=device-width, initial-scale=1.0">
        </head>
        <body>
    	
    <h1> Sign Up</h1>
    	
    	
    	<form method="post" action="register.php">
    	<table>
    	<tr>
    	<td>Name :</td>
    	<td><input type="text" name="name" class="textinput"></td>
    	</tr>
    	<tr>
    	<td>Username :</td>
    	<td><input type="text" name="username" class="textinput"></td>
    	</tr>
    	<tr>
    	<td>Email :</td>
    	<td><input type="email" name="email" class="textinput"></td>
    	</tr>
    	<tr>
    	<td>Password :</td>
    	<td><input type="password" name="password" class="textinput"></td>
    	</tr>
    	<tr>
    	<td>Confirm Password :</td>
    	<td><input type="password" name="password2" class="textinput"></td>
    	</tr>
    	<tr>
    	<td>Contact :</td>
    	<td><input type="number" name="contact" class="textinput"></td>
    	</tr>
    	<tr>
    	<td></td>
    	<td><input type="submit" name="register_btn" value="Register"></td>
    	</tr>
    	<tr>
    	<td></td>
    	<td>Already a member <a href="login.php">SIGN IN</a></td>
    	</tr>
    	
    	</table>
    	
    	</form>
        </body>
    </html>

Whenever i register using this page the code doesent do anything 
what should i do so that it works properly? I want that when it submits it adds the details of the form in the database which is apparantly the biggest problem
need to sort it out asap