comments hidden

I installed your plugin and configured the shortcode. All worked well except the comments function for all posts was then hidden. I deactivated the plugin and the comments reappeared for a moment. But your plugin reinstalled itself. I’ve deactivated it three times and deleted the files and it keeps reappearing. It has become a spam app. How do I get rid of this thing?

https://wordpress.org/plugins/latest-post-shortcode/