Hi,
it seems that your website isn’t enqueuing css and js from the plugin.
Please try to switch to the default theme. If it works it means that the bug is caused by the plugin. I cannot found your theme’s style.css, so make sure to disable any css/js optimizer in your WordPress website.
If you have to manually enqueue css and js, try adding the following in your <head>
section:
<link rel="stylesheet" id="basecss-css" href="https://prismaspa.net/wp-content/plugins/eu-cookie-law/css/style.css?ver=4.2.2" type="text/css" media="all">
<script type="text/javascript" src="https://prismaspa.net/wp-content/plugins/eu-cookie-law/js/scripts.js?ver=4.2.2"></script>
Again, this is not normal. If possible, in this case, i would fix the theme because the plugin itself uses the correct way for enqueuing css and js.
Let me know if you are able to solve this issue.