Gravity Forms has a CAPTCHA feature that you can add. BPS JTC hooks into these forms only: WordPress Login, Register, Lost Password, Theme Comment Forms. Multisite Register Form. BuddyPress Register Form. BuddyPress Sidebar Login Form. WooCommerce Login and Register Forms.
Unfortunatelly, this is not applicable in my case. There is simple post, and captcha is also prevent usability and accessibility. Do you have recommendation for my problem? Maybe a .htaccess code or anything else?
Try Google reCAPTCHA. A CAPTCHA is the best protection for forms. The only thing you could do with htaccess code is block by IP addresses and that is of course a completely ineffective method since hackers and spammers can switch to many different IP addresses.