You need to Pay! Plugin is not free as advertised!

Hello.

Thank you for your review.

The fact that the plugin has a premium type service is mentioned in the plugin annotation and in its WordPress catalog description:
https://wordpress.org/plugins/cleantalk-spam-protect/

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CleanTalk is a plugin of free code which works with the Cloud Anti-Spam Service: https://en.wikipedia.org/wiki/Software_as_a_service

These types of plugins are allowed in the WordPress directory, please look here:
https://wordpress.org/support/topic/is-this-plugin-free-to-use-after-trial/#post-5336850

We offer the most fastest, strongest, wide functionality anti-spam for any WordPress users for a very cheap price.

All the best.