How to fix this error : Connection could not be established with host "mailpit:1025"

I've initially posted this on StackOverflow, I've had answers that didn't help, and my post got hidden because of a duplicate that didn't answer my problem at all. Full error : Connection could not be established with host "mailpit:1025": stream_socket_client(): php_network_getaddresses: getaddrinfo for mailpit failed: Temporary failure in name resolution I'm doing a website using laravel 10 and docker, and when trying to use Laravel's Mail, i get this error. Here is my current configuration and code (just the mail parts) :

.env :
MAIL_DRIVER=smtp
MAIL_ACCOUNT=gmail
MAIL_HOST=smtp.gmail.com
MAIL_PORT=587
MAIL_USERNAME=finderwebsite1@gmail.com
MAIL_PASSWORD=g***************
MAIL_ENCRYPTION=ssl
MAIL_FROM_ADDRESS="finderwebsite1@gmail.com"
MAIL_FROM_NAME="Finder"

SignUp mail class :

<?php

namespace App\Mail;

use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Mail\Mailable;
use Illuminate\Mail\Mailables\Content;
use Illuminate\Mail\Mailables\Envelope;
use Illuminate\Queue\SerializesModels;

class SignUp extends Mailable
{
    use Queueable, SerializesModels;

    private $data=[];
    public function __construct($data)
    {
        $this->data=$data;
    }

    /**
     * Get the message envelope.
     */
    public function envelope(): Envelope
    {
        return new Envelope(
            subject: 'Sign Up',
        );
    }

    /**
     * Get the message content definition.
     */
    public function content(): Content
    {
        return new Content(
            view: 'emails.SignUpView',
        );
    }

    /**
     * Get the attachments for the message.
     *
     * @return array<int, \Illuminate\Mail\Mailables\Attachment>
     */
    public function attachments(): array
    {
        return [];
    }

    public function build(){
        return $this->from('finderwebsite1@gmail.com','Finder')
        ->subject($this->data['subject'])->view('emails.SignUpView')->with('data',$this->data);
    }
}

MailController :

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Mail;
use App\Mail\SignUp;

class MailController extends Controller
{
    public function signUp(){
        $data=[
            'subject'=>'bienvenue sur Finder !',
            'body'=>'tranquille ? bien ? !'
            
        
        ];
        try{
            Mail::to('hernandez.mathieu19@gmail.com')->send(new SignUp($data));
            return response()->json(['Great ! your soul is mine ^w^']);
        }catch(exception $e){
            return $e;
        }
    }
}

}

web.php :

<?php

use Illuminate\Support\Facades\Route;
use App\Http\Controllers\AuthController;
use App\Http\Controllers\AdminController;
use App\Http\Controllers\MailController;
...
Route::get('/welcome-mail', [MailController::class,'signUp']);
...

And I simply go to localhost/welcome-mail.

I have tried multiple solutions like using Mailtrap, using smtp, just localhost, but this error is still there. I've also followed different tutorials, but I have a feeling the issue is with Docker (just a guess). I've also tried manually changing config.php, which seems to be using mailpit. Maybe i didn't change it well.

Dockerfile :

FROM php:8.2-apache

# Install dependencies
RUN apt-get update && \
    apt-get install -y \
    libzip-dev \
    zip

# Enable mod_rewrite
RUN a2enmod rewrite

# Install PHP extensions
RUN docker-php-ext-install pdo_mysql zip

ENV APACHE_DOCUMENT_ROOT=/var/www/html/public
RUN sed -ri -e 's!/var/www/html!${APACHE_DOCUMENT_ROOT}!g' /etc/apache2/sites-available/*.conf
RUN sed -ri -e 's!/var/www/!${APACHE_DOCUMENT_ROOT}!g' /etc/apache2/apache2.conf /etc/apache2/conf-available/*.conf

# Copy the application code
COPY . /var/www/html

# Set the working directory
WORKDIR /var/www/html

# Install composer
RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer

# Install project dependencies
RUN composer install

# Set permissions
RUN chown -R www-data:www-data /var/www/html/storage /var/www/html/bootstrap/cache

configs/mail.php :

...
'mailers' => [
        'smtp' => [
            'transport' => 'smtp',
            'url' => env('MAIL_URL'),
            'host' => env('MAIL_HOST', 'smtp.gmail.com'),
            'port' => env('MAIL_PORT', 587),
            'encryption' => env('MAIL_ENCRYPTION', 'tls'),
            'username' => env('MAIL_USERNAME'),
            'password' => env('MAIL_PASSWORD'),
            'timeout' => null,
            'local_domain' => env('MAIL_EHLO_DOMAIN'),
        ],
...

cache/config.php :

...
'mail' => 
  array (
    'default' => 'smtp',
    'mailers' => 
    array (
      'smtp' => 
      array (
        'transport' => 'smtp',
        'url' => NULL,
        'host' => 'mailpit',
        'port' => '1025',
        'encryption' => NULL,
        'username' => NULL,
        'password' => NULL,
        'timeout' => NULL,
      ),
      'ses' => 
      array (
        'transport' => 'ses',
      ),
      'postmark' => 
      array (
        'transport' => 'postmark',
      ),
      'mailgun' => 
      array (
        'transport' => 'mailgun',
      ),
      'sendmail' => 
      array (
        'transport' => 'sendmail',
        'path' => '/usr/sbin/sendmail -bs -i',
      ),
      'log' => 
      array (
        'transport' => 'log',
        'channel' => NULL,
      ),
      'array' => 
      array (
        'transport' => 'array',
      ),
      'failover' => 
      array (
        'transport' => 'failover',
        'mailers' => 
        array (
          0 => 'smtp',
          1 => 'log',
        ),
      ),
      'roundrobin' => 
      array (
        'transport' => 'roundrobin',
        'mailers' => 
        array (
          0 => 'ses',
          1 => 'postmark',
        ),
      ),
    ),
    'from' => 
    array (
      'address' => 'hello@example.com',
      'name' => 'Laravel',
    ),
    'markdown' => 
    array (
      'theme' => 'default',
      'paths' => 
      array (
        0 => '/var/www/html/resources/views/vendor/mail',
      ),
    ),
  ),
...

I don't know if I should try to modify cache/config.php again.