route cannot be found while reverse-routing.

PHP Code:

//1. Named route
$routes->get('cat/edit/(:num)', 'CatController::edit/$1', ['as' => 'cat.edit']);

redirect()->route('cat.edit', [$id])

//2. Controller&method (with namespace)
redirect()->route('\App\Controllers\CatController::edit', [$id])

//3. Url
redirect()->to('admin/cat/edit/' . $id) 


Note that the withInput() method already adds validation error data.
To get errors you need:

PHP Code:

// init session (Even though it looks stupid in terms of practicality, but otherwise will not work.)
session();
// get validator instance
$validation = Services::validation();
// get errors 
$validation->getErrors();