Target class [SettingsController] does not exist. code example

Example 1: Target class [UserController] does not exist.

Note: don't forget to import (use) your controller in the routes(web.php) file at the top. Like:
use App\Http\Controllers\PagesController;

Route::get('/',[PagesController::class, 'index']);

Example 2: Target class [PlayerController] does not exist.

//add controller path
Route::get('/players', 'App\Http\Controllers\PlayerController@index');