Ajax call not working for my custom plugin

I need help in getting ajax to work in my custom wordpress plugins

These are the steps i followed

step one

// STEP ONE:
// I added the jquery script and localized it in my plugin base file
function add_js() {
 
	
	wp_enqueue_script( 'front_script',  plugins_url('assets/js/frontend.js', __FILE__), array( 'jquery' ) );
	wp_enqueue_script( 'test_script',  plugins_url('assets/js/test.js', __FILE__), array( 'jquery' ) );
	wp_localize_script( 'test_script', 'myobject', array( 'ajaxurl' => admin_url( 'admin-ajax.php' )));
	wp_enqueue_script('test_script');
}

add_action( 'wp_enqueue_scripts', 'add_js' );

// STEP TWO:
// I created a php validation form - test.php
add_action( 'wp_ajax_validatetest', 'validatetest' );
add_action( 'wp_ajax_nopriv_validatetest', 'validatetest' );	
function validatetest(){
	if(isset($_POST['submit_testpost'])){
		$value = !empty($_POST['testpost']) ? $_POST['testpost'] : '';
		
			if(empty($value)){
				$reply = array('paul' => 'test-error', 'message' => 'can not be empty');
				print_r(json_encode($reply, true));
				
			}
			
			elseif($value != 'money'){
				$reply = array('paul' => 'test-error', 'message' => 'Make more money');
				print_r(json_encode($reply));
				
				
			}
			else{
				
				$reply = array('paul' => 'test-success', 'message' => 'Your money has been paid into your account');
				print_r(json_encode($reply, true));
				
			}

	}		
		
}

// STEP THREE
// I ADDED THE HTML IN test.php
function formy(){
		$value = !empty($_POST['testpost']) ? $_POST['testpost'] : '';
		$milk = '<div class="testdiv"><form action="" method="post">
		<input type="text" name="testpost" value="'.$value.'">
		<input type="submit" name="submit_testpost" value="Submit" class="submit_testpost"></form></div>
		';
		
		echo $milk;
	}
	
	
	
	
	
// STEP FOUR
// I ADDED THE JQUERY SCRIPT - in assets/js/test.js

jQuery(document).ready(function($) {
$(document).ready(function() {
		
	$('.submit_testpost').on("click", function(){
		
		
		var data = {
			'action': 'validatetest'
		};

		jQuery.post(myobject.ajaxurl, data, function(response) {
			
				var data = jQuery.parseJSON(response);	
				if(data.paul == 'test-success'){
					
				alert(data.paul);
					
				}else{
					
				alert('wait guy');
				}
		});
		

		
	});

	 e.preventDefault();
	
});
});

But for some unknown reason it seems not to be working, the alert or both success or error is not showing, as if the call was not made
What am i doing wrong, and secondly the page reloads once the submit button is clicked but i want to stop the page from reloading
I only want it to exit on success but echo error message on failure but not reload page, which was what i thought preventDefault does.