Lost authentication data and wrong request method

Hello,

I connect to a laravel site through another portal site that sends me to my home page with a token that allows me to authenticate myself.

It works perfectly with my development App on my PC, but on the pre-production server, I have an error "The POST method is not supported for this route" and if I change my route to post, I have a error 419 Page Expired.

I don't understand why my route is considered to be in post. If I reload the page by pressing enter in the url, the page loads normally but I lose my authentication data.

I tried to create a redirect route but I have the same problem

Route::redirect('/Auth', '/Home');

My AuthServiceprovider :

<?php

namespace App\Providers;

use App\Models\User;
use App\Policies\VTCPolicy;
use Firebase\JWT\ExpiredException;
use Firebase\JWT\JWT;
use Firebase\JWT\SignatureInvalidException;
use GuzzleHttp\Client as HTTPClient;
use Illuminate\Foundation\Support\Providers\AuthServiceProvider as ServiceProvider;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Storage;
use Illuminate\Http\Request;
use Session;

class AuthServiceProvider extends ServiceProvider
{
    /**
     * The policy mappings for the application.
     *
     * @var array
     */
    protected $policies = [
        VTCPolicy::class => 'App\Policies\VTCPolicy',
    ];

    /**
     * Register any authentication / authorization services.
     *
     * @return void
     */
    public function boot()
    {
        $this->registerPolicies();
         $publicKey = $this->getPublicKey();
         $user = null;
         $request = $this->app->request;

        try {
             $jwt = $request->token;
             $data = JWT::decode($jwt, $publicKey, array('RS256'));
             $user = json_decode(json_encode((array) $data));
        }
        catch (SignatureInvalidException | \DomainException $e)
        {
            $request->attributes->set('errorToken', ['status' => 'Token is Invalid', 'code' => 401]);
        }
        catch (ExpiredException $e)
        {
            $request->attributes->set('errorToken', ['status' => 'Token is Expired', 'code' => 401]);

        }
        catch (\UnexpectedValueException $e)
        {
            $request->attributes->set('errorToken', ['status' => 'Authorization Token not found', 'code' => 401]);
        }
        catch (\Exception $e)
        {
            $request->attributes->set('errorToken', ['status' => 'Unknown Error', 'code' => 500]);
        }

        if ($user !== null)
        {
            $userDB = User::where('mbr_login', $user->username)->first();

            if ($userDB != null)
            {
                Auth::login($userDB);
                return $userDB;
            }
            else
            {
                dd("Error 403");
            }
        }
    }

     private function getPublicKey()
     {
         $baseUri = 'public key URL';
         $client = new HTTPClient(['base_uri' => $baseUri, 'verify' => false]);
         $response = $client->request('GET', 'publicKey');
         $publicKey = (string) $response->getBody();
         return $publicKey;
     }
 }