developing an ajax login plugin and getting reauth=1

I’m developing a plugin for ajax login with modal popup.
On localhost it’s all working just fine I can go from frontend to backend without any issue.
However, when I login on the internet website everything is fine untill I navigate on the frontend but when I try to go to wordpress admin dashboard (or to any admin section) I get the wordpress login form again with the URL string ending with &reauth=1 and I have to login again.

I’ve searched around the internet and the issue seems to be related to the auth_cookie but still haven’t found a solution.

You can try yourself with credentials: demo, demo

here’s the function I’ve written to login for ajax and no ajax case and how it’s called back.

function auth_user_login_no_ajax($action,$user_login,$password,$login) {

		//first clear all auth cookies
		//wp_clear_auth_cookie();

		//if login is called by ajax call die the function
	    if ( is_user_logged_in() && $action == 'ajaxlogin' ) {
	    	$output = json_encode(array(
				'loggedin'=>true, 
				'message'=> $login.__(' successful, redirecting...','sw-ajax-login'),
				));
			die($output);
			return;
		}

		//impostazione per redirect pagina
		$page_to_redirect = swal_page_to_redirect();

		//get remember credentials option
		$swal_login_remember_credentials     = intval(get_option('swal_login_remember_credentials',SWAL_LOGIN_REMEMBER_CREDENTIALS));

		$info = array();
	    $info['user_login'] = $user_login;
	    $info['user_password'] = $password;

	    //check if it has to remember credentials
	    if ($swal_login_remember_credentials == 0) {
	    	$info['remember'] = true;
	   	} else if ($swal_login_remember_credentials == 1) {
	    	$info['remember'] = false;
	   	} else if ($swal_login_remember_credentials == 2) {
	   		if (isset($_POST['rememberme'])) {
	   			if ($_POST['rememberme']) {
	   				$info['remember'] = true;
	   			} else {
	   				$info['remember'] = false;
	   			}
	   			
	   		}
	    	
	   	}
		
		$user_signon = wp_signon( $info, false );

	    if ( is_wp_error($user_signon) ){
			$output = json_encode(array(
				'loggedin'=>false,
				'message'=> __('Wrong username or password.','sw-ajax-login')
				));
	    } else {
	    	wp_set_auth_cookie( $user_signon->ID, $info['remember'], false);
			wp_set_current_user($user_signon->ID);
			
			$output = json_encode(array(
				'loggedin'=>true, 
				'message'=> $login.__(' successful, redirecting...','sw-ajax-login'),
				));
			
			//if login arrive from no ajax request then redirect
			if ( $action == 'login' ) {
				
				wp_redirect( $page_to_redirect );
			}
	    }

	    //if login is called by ajax call die the function
	    if ( $action == 'ajaxlogin' ) {

			die($output);

		} else if ( $action == 'login' ) {

			$GLOBALS['sw_login_json'] = $output;
		}
}

When the function is called, i’ve shortened to make it more readable.

add_action( 'after_setup_theme', 'swal_auth_user_no_ajax' );

function swal_auth_user_no_ajax() {

	/**
	 * Verify if the request arrive via POST
	 */ 
	if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['action'])) {

		$action = $_POST['action'];

		/**
		 * Login function
		 */ 

		if ( $action == 'ajaxlogin' || $action == 'login') {
			//if function is called from normal POST request check nonce in the regular way
			if ( $action == 'ajaxlogin' ) {

				// check the nonce in case of ajax request
	    		check_ajax_referer( 'ajax-login-nonce', 'security' );

			} else if ( $action == 'login' ) {

				$nonce = $_POST['security'];
				if ( ! wp_verify_nonce( $nonce, 'ajax-login-nonce' ) ) {
				     return; 
				}

			}

			auth_user_login_no_ajax($action,$_POST['username'],$_POST['password'],'Login');
		}

Thanks

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