Symfony 4 - The autoloader expected class […] to be defined in file

I'm trying to add an old Bundle that I have built on Symfony 3.* to Symfony 4 but I get this error:

The autoloader expected class "App\SBC\TiersBundle\Controller\ChantierController" to be defined in file "/Applications/MAMP/htdocs/Projects/HelloSymfony4/vendor/composer/../../src/SBC/TiersBundle/Controller/ChantierController.php". The file was found but the class was not in it, the class name or namespace probably has a typo in /Applications/MAMP/htdocs/Projects/HelloSymfony4/config/services.yaml (which is loaded in resource "/Applications/MAMP/htdocs/Projects/HelloSymfony4/config/services.yaml").

It seems like the framework did not recognise the namespace of the bundle so I did these steps:
In config/bundle.php I added the third line:

return [
    Symfony\Bundle\FrameworkBundle\FrameworkBundle::class => ['all' => true],
    Symfony\Bundle\TwigBundle\TwigBundle::class => ['all' => true],
    \SBC\TiersBundle\TiersBundle::class => ['all' => true], // this one
    Symfony\Bundle\WebProfilerBundle\WebProfilerBundle::class => ['dev' => true, 'test' => true],
];

And in composer.json I added the first line in autoload section:

"autoload": {
        "psr-4": {
            "SBC\\": "src/SBC/",
            "App\\": "src/"

        }
    },

Because the namespace of my Bundle starts with SBC\, and I have launched composer dump-autoload in the console.

<?php

namespace SBC\TiersBundle;

use Symfony\Component\HttpKernel\Bundle\Bundle;

class TiersBundle extends Bundle
{
}

ChantierController.php:

namespace SBC\TiersBundle\Controller;

use SBC\TiersBundle\Entity\Chantier;
use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\HttpFoundation\Request;


class ChantierController extends Controller
{
...
}

And this is my Bundle under /src:

Unfortunately still facing the same error, how can I fix it and thanks in advance.

UPDATE: config/services.yaml:

# Put parameters here that don't need to change on each machine where the app is deployed
# https://symfony.com/doc/current/best_practices/configuration.html#application-related-configuration
parameters:

services:
    # default configuration for services in *this* file
    _defaults:
        autowire: true      # Automatically injects dependencies in your services.
        autoconfigure: true # Automatically registers your services as commands, event subscribers, etc.
        public: false       # Allows optimizing the container by removing unused services; this also means
                            # fetching services directly from the container via $container->get() won't work.
                            # The best practice is to be explicit about your dependencies anyway.

    # makes classes in src/ available to be used as services
    # this creates a service per class whose id is the fully-qualified class name
    SBC\:
        resource: '../src/SBC/*'
        exclude: '../src/SBC/TiersBundle/{Entity,Migrations,Tests}'

    SBC\TiersBundle\Controller\:
        resource: '../src/SBC/TiersBundle/Controller'
        tags: ['controller.service_arguments']

    App\:
        resource: '../src/*'
        exclude: '../src/{Entity,Migrations,Tests}'

    # controllers are imported separately to make sure services can be injected
    # as action arguments even if you don't extend any base controller class
    App\Controller\:
        resource: '../src/Controller'
        tags: ['controller.service_arguments']

    # add more service definitions when explicit configuration is needed
    # please note that last definitions always *replace* previous ones