Invalid plugin

[catalin-teodorescu-te]

I did a composer require fatfish/notification, all went fine.
But when I went to admin interface and clicked on the install button, I got this error:
No plugin exists with the handle "notification".
Same error appears when I try installing it from the CLI using:
craft install/plugin fatfish/notification,
craft install/plugin fatfish/Notification,
craft install/plugin notification or
craft install/plugin Notification.