code error when creating controller in laravel

code error when creating controller in laravel php artisan make:Controller KmsController

RuntimeException
Unable to detect application namespace.
Illuminate\Console\GeneratorCommand::rootNamespace()

and I tried: composer dump-autoload

In JsonFile.php line 340:

"./composer.json" does not contain valid JSON
Parse error on line 65:
...fer-stable": true}{ "require": {
--------------------^
Expected one of: 'EOF', '}', ',', ']'

If your json you posted is exactly like that, your error is at the bottom, see this part:

{
    "config": {
        "optimize-autoloader": true,
        "preferred-install": "dist",
        "sort-packages": true
    },
    "minimum-stability": "dev",
    "prefer-stable": true
} // HERE IS THE ERROR
{
    "require": {
        "phpoffice/phpspreadsheet": "^1.23"
    },
    "config": {
        "platform": {
            "php": "7.3"
        }
    }
}

You have to move the text inside the require (at the bottom) into the top where you also have require, same for config...

Your JSON should be like this:

{
    "name": "laravel/laravel",
    "type": "project",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "require": {
        "php": "^7.3|^8.0",
        "consoletvs/charts": "6.*",
        "fruitcake/laravel-cors": "^2.0",
        "guzzlehttp/guzzle": "^7.0.1",
        "ladumor/laravel-pwa": "^0.0.3",
        "laravel/framework": "^8.75",
        "laravel/sanctum": "^2.11",
        "laravel/tinker": "^2.5",
        "phpoffice/phpspreadsheet": "^1.25",
        "phpoffice/phpspreadsheet": "^1.23"
    },
    "require-dev": {
        "facade/ignition": "^2.5",
        "fakerphp/faker": "^1.9.1",
        "laravel/sail": "^1.0.1",
        "mockery/mockery": "^1.4.4",
        "nunomaduro/collision": "^5.10",
        "phpunit/phpunit": "^9.5.10"
    },
    "autoload": {
        "psr-4": {
            "App\\": "app/",
            "Database\\Factories\\": "database/factories/",
            "Database\\Seeders\\": "database/seeders/"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "Tests\\": "tests/"
        }
    },
    "scripts": {
        "post-autoload-dump": [
            "Illuminate\\Foundation\\ComposerScripts::postAutoloadDump",
            "@php artisan package:discover --ansi"
        ],
        "post-update-cmd": [
            "@php artisan vendor:publish --tag=laravel-assets --ansi --force"
        ],
        "post-root-package-install": [
            "@php -r \"file_exists('.env') || copy('.env.example', '.env');\""
        ],
        "post-create-project-cmd": [
            "@php artisan key:generate --ansi"
        ]
    },
    "extra": {
        "laravel": {
            "dont-discover": []
        }
    },
    "config": {
        "optimize-autoloader": true,
        "preferred-install": "dist",
        "sort-packages": true,
        "platform": {
            "php": "7.3"
        }
    },
    "minimum-stability": "dev",
    "prefer-stable": true
}

BUT, you can see you now have the same package, twice, with 2 different versions:

"require": {
    "php": "^7.3|^8.0",
    "consoletvs/charts": "6.*",
    "fruitcake/laravel-cors": "^2.0",
    "guzzlehttp/guzzle": "^7.0.1",
    "ladumor/laravel-pwa": "^0.0.3",
    "laravel/framework": "^8.75",
    "laravel/sanctum": "^2.11",
    "laravel/tinker": "^2.5",
    "phpoffice/phpspreadsheet": "^1.25",
    "phpoffice/phpspreadsheet": "^1.23"
},

You will have to know if phpoffice/phpspreadsheet needs to be ^1.25 or ^1.23. I will assume using 1.25 is fine