Using .htaccess you can block IP from where you are getting spam comments on WordPress in various form regularly and thus you can block spam comments.
Akismet WordPress plugin is one of the plugin by which you can protect comment spam.
When you will get comments constantly from unknown sender you can see that few IP’s are sending constantly spam comments.
Comment spam is a common fact of our technical life if you have a blog definitely. You have not only accurate built-in tools to prevent comment spam in WordPress, but, there are also so many comment spam protection and defense plugins and functions to choose from if you feel you need additional coverage and protection to your blog.
Read Also: Top 5 most popular wordpress plugins
There is no actual “one size fits all” method which will protect your website comments but, they use more tactics. So, consider using more than one defense. Note to remember that spammers like to change the way they attack different times so you must keep your choices updated.
So the best and easiest way to protect this is to block the IP’s using .htaccess method.
<Limit GET POST> order allow,deny deny from 18.104.22.168 deny from 22.214.171.124 allow from all </Limit>
This is easiest way to protect your WordPress blog from spammers.