Laravel and Mailgun - laravel

Question

I am trying to set up emailing feature on my laravel project. I got everything settled up but somehow I get this error
Swift_TransportException
Cannot send message without a sender address.
Here is my mail.php script.
'mailers' => [
'smtp' => [
'transport' => 'smtp',
'host' => env('MAIL_HOST', 'smtp.mailgun.org'),
'port' => env('MAIL_PORT', 587),
'encryption' => env('MAIL_ENCRYPTION', 'tls'),
'username' => env('MAIL_USERNAME'),
'password' => env('MAIL_PASSWORD'),
'timeout' => null,
],
'mailgun' => [
'transport' => 'mailgun',
],
'sendmail' => [
'transport' => 'sendmail',
'path' => '/usr/sbin/sendmail -bs',
],
'log' => [
'transport' => 'log',
'channel' => env('MAIL_LOG_CHANNEL'),
],
'array' => [
'transport' => 'array',
],
],
.env file
MAIL_MAILER=mailgun
MAIL_HOST=smtp.mailgun.org
MAIL_PORT=2525
MAIL_USERNAME=postmaster#sandbox*****************.mailgun.org
MAIL_PASSWORD=**********************************
MAIL_ENCRYPTION=tls
MAIL_FROM_ADDRESS=null
MAIL_FROM_NAME="${APP_NAME}"
ReportInfrastructure.php
namespace App\Mail;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Mail\Mailable;
use Illuminate\Queue\SerializesModels;
class ReportInfrastructure extends Mailable
{
use Queueable, SerializesModels;
/**
* Create a new message instance.
*
* #return void
*/
public function __construct()
{
//
}
/**
* Build the message.
*
* #return $this
*/
public function build()
{
return $this->from('infor#mise.gov.ki')
->markdown('emails.infrastructure');
}
}
infrastructure.blade.php
#component('mail::message')
# Critical Infrastructure Name
PLEASE NOTE: You're receiving this email because our records indicate that above Infrastructure is in critical condition and need to address asap.
Click the on the button below to show more details of this issue.
#component('mail::button', ['url' => ''])
Button Text
#endcomponent
Thanks,<br>
{{ config('app.name') }}
#endcomponent
Route
Route::get('/email', function () {
Mail::to('email#email.com')->send(new ReportInfrastructure());
return new ReportInfrastructure();
});
Can someone point me out what I did wrong?