I found the reason,a developer added this to the mail config file

'to' => [
        'address' => env('MAIL_TO_ADDRESS', '[email protected]'),
        'name' => env('MAIL_TO_NAME', 'Name'),
    ]

Because in the beginning the website was not supposed to send emails to users, only one person would be notified. this was overwritten the Mail::to($user->email) Now everything works fine