Mailing configuration can been seen at 2 places:

1. .env file
2. mail.php file located in config folder

You can update either of them, but it is strictly recommended to edit the .env file so as to avoid touching the default configurations.

Open .env file. You will see the mail configs in the bottom like so:

MAIL_DRIVER=smtp
MAIL_HOST=mailtrap.io
MAIL_PORT=2525
MAIL_USERNAME=null
MAIL_PASSWORD=null
MAIL_ENCRYPTION=null

Now, login to your mailtrap.io account. From the Integrations dropdown, you need to select the Laravel option. When selected, the configs are provided below like this:

return array(
  "driver" => "smtp",
  "host" => "mailtrap.io",
  "port" => 2525,
  "from" => array(
      "address" => "[email protected]",
      "name" => "Example"
  ),
  "username" => "your_username",
  "password" => "your_password",
  "sendmail" => "/usr/sbin/sendmail -bs",
  "pretend" => false
);

Now open the mail.php file:

Go down to line number 57, it should have 'from' => ['address' => null, 'name' => null],. You need to replace this with what is provided in the mailtrap.io config.

So the updated from should be 'from' => ['address' => '[email protected]', 'name' => 'Example'],.

Now, in your .env file, update the MAIL_USERNAME and MAIL_PASSWORD with the your_username and your_password respectively.

So, your mailing config in .env file should like:

MAIL_DRIVER=smtp
MAIL_HOST=mailtrap.io
MAIL_PORT=2525
MAIL_USERNAME=your_username
MAIL_PASSWORD=your_password
MAIL_ENCRYPTION=null

Done. You should now see the mails functioning without any further issues. Hope this helps you out.

Cheers.