include('components/cls-forgot-password.php'); // including custom forgot password shortcode class
$CLS_FORGOT_PASSWORD = new CLS_FORGOT_PASSWORD; // invoking the access for the cls_forgot_password_form shortcode

function redirect_forgot_page(){
	// Store for checking if this page equals wp-login.php
    $page_viewed = basename( $_SERVER['REQUEST_URI'] );

    if( $page_viewed == "wp-login.php?action=lostpassword" ) {
        wp_redirect( '/forgot');
        exit();
    }
}

add_filter("init", "redirect_forgot_page");





<?php
if ( ! defined( 'ABSPATH' ) ) { die; }

if ( ! class_exists( 'CLS_FORGOT_PASSWORD' ) ) {

	class CLS_FORGOT_PASSWORD {
		function __construct() {
			add_shortcode('cls_forgot_password_form', array( $this, 'shortcode_init') );
		}
		public function shortcode_init($atts, $content = null) {
			ob_start();
			$this->process();
			$this->form();
			return ob_get_clean();

		}
		private function form() {
			?>
			<p>Please enter your username or email address. You will receive a link to create a new password via email.</p>
			<hr />
			<div class="page-restrict-output">

				<form method="post" action="<?php echo $_SERVER['REQUEST_URI']; ?>">
					<input type="hidden" name="action" value="reset" />

					<div class="login-form">
						<div class="form-group">
							<?php $user_login = isset( $_POST['user_login'] ) ? $_POST['user_login'] : ''; ?>
							<label class="login-field-icon fui-user" for="login-name">Username: </label>
							<input name="user_login" type="text" class="login-field" value="" placeholder="Username or email address" id="login-name" />
						</div>

				        <p align="center">
							<input class="btn btn-default" type="submit"  name="dlf_submit" value="Get New Password" />
						</p>
					</div>
				</form>

			</div>

			<?php
		}
		private function process() {
		    global $wpdb;

		    $error = '';
		    $success = '';

		    // check if we're in reset form
		    if( isset( $_POST['action'] ) && 'reset' == $_POST['action'] )
		    {
		        $email = trim($_POST['user_login']);

		        if( empty( $email ) ) {
		            $error = 'Enter a username or e-mail address..';
		        } else if( ! is_email( $email )) {
		            $error = 'Invalid username or e-mail address.';
		        } else if( ! email_exists($email) ) {
		            $error = 'There is no user registered with that email address.';
		        } else {

		            // lets generate our new password
		            $random_password = wp_generate_password( 12, false );

		            // Get user data by field and data, other field are ID, slug, slug and login
		            $user = get_user_by( 'email', $email );

		            $update_user = wp_update_user( array (
		                    'ID' => $user->ID,
		                    'user_pass' => $random_password
		                )
		            );

		            // if  update user return true then lets send user an email containing the new password
		            if( $update_user ) {
		                $to = $email;
		                $subject = 'Your new password';
		                $sender = get_option('name');

		                $message = 'Your new password is: '.$random_password;

		                $headers[] = 'MIME-Version: 1.0' . "\r\n";
		                $headers[] = 'Content-type: text/html; charset=iso-8859-1' . "\r\n";
		                $headers[] = "X-Mailer: PHP \r\n";
		                $headers[] = 'From: '.$sender.' < '.$email.'>' . "\r\n";

		                $mail = wp_mail( $to, $subject, $message, $headers );
		                if( $mail )
		                    $success = 'Check your email address for you new password.';

		            } else {
		                $error = 'Oops something went wrong updaing your account.';
		            }

		        }

		        if( ! empty( $error ) )
		            echo '<div class="error_login"><strong>ERROR:</strong> '. $error .'</div>';

		        if( ! empty( $success ) )
		            echo '<div class="updated"> '. $success .'</div>';
		    }
		}
	}
}