Lae/app/Http/Middleware/ValidateUserIfBanned.php

<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\Request;

class ValidateUserIfBanned
{
    /**
     * Handle an incoming request.
     *
     * @param \Illuminate\Http\Request                                                                          $request
     * @param \Closure(\Illuminate\Http\Request): (\Illuminate\Http\Response|\Illuminate\Http\RedirectResponse) $next
     *
     * @return \Illuminate\Http\Response|\Illuminate\Http\RedirectResponse
     */
    public function handle(Request $request, Closure $next)
    {
        $user = $request->user();
        if ($user) if ($user->banned_at !== null) {
            return redirect()->route('banned');
        }

        return $next($request);
    }
}