Laravel 5.6 SMTP Connection could not be established with host smtp.mailtrap.io

.env file:

MAIL_DRIVER=smtp
MAIL_HOST=smtp.mailtrap.io
MAIL_PORT=2525
MAIL_USERNAME=myuser
MAIL_PASSWORD=mypassword
MAIL_ENCRYPTION=TLS

I have done the following command to clear cache and config:

php artisan cache:clear
php artisan config:cache
php artisan config:clear

I get the following error

Connection could not be established with host smtp.mailtrap.io [php_network_getaddresses: getaddrinfo failed: No such host is known.

I have also tried restaring local development server.

via Chebli Mohamed