Check out example codes for "Swift_TransportException Cannot send message without a sender address". It will help you in understanding the concepts better.

Code Example 1

php artisan config:cache

Code Example 2

MAIL_DRIVER=smtp
MAIL_HOST=smtp.mailtrap.io
MAIL_PORT=2525
MAIL_USERNAME=your_username
MAIL_PASSWORD=your_password
MAIL_ENCRYPTION=null
[email protected] **here**
MAIL_FROM_NAME="${APP_NAME}"

Code Example 3

php artisan view:clear;
php artisan config:cache;
php artisan cache:clear;
php artisan route:cache;

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