I received email with subject LARAVEL SMTP CRACK | HOOST

Today i get email with subject "LARAVEL SMTP CRACK | HOOST" I use laravel framework 5.8. My .env include

APP_ENV = production
APP_DEBUG = false

and

MAIL_DRIVER=smtp
MAIL_HOST=smtp.domain.site
MAIL_PORT=2525
MAIL_USERNAME=xxx
MAIL_PASSWORD=xxxx
MAIL_ENCRYPTION=tls

what can i do ? was my site hacked?

via Chebli Mohamed