Fatal error: Uncaught TypeError: call_user_func(): Argument #1 ($callback) must be a valid callback

[frankndungu]

Hey guys if you are following this the tutorial you should know that PHP 8.1 does not accept

$router->get('/products', [ProductController::class, 'index']);

But it accepts;

$router->get('/products', [new ProductController(), 'index']);

[frankndungu]

After changing it it worked for me.