Uncaught TypeError: blockquote__tweet[0] is undefined

This error shows up when I do a live test in Google Console. Looks like uagb- is missing in a couple of places??

I have deactivated the social block but the error still appears. Which brings me to question, why is the Javascript showing up if that block is deactivated?

Below code is from my page source code.

<script type="text/javascript" id="uagb-script-frontend">document.addEventListener("DOMContentLoaded", function(){ 			var selector = document.querySelectorAll( '.uagb-block-93a9cc1d' );
			var blockquote__tweet = selector[0].getElementsByClassName("uagb-blockquote__tweet-button");
			blockquote__tweet[0].addEventListener("click",function(){
				var content = selector[0].getElementsByClassName("uagb-blockquote__content")[0].innerText;
				var request_url = "https://twitter.com/share?url="+ encodeURIComponent("' . . '")+"&text="+content+"&via="+("' .  . '"); 
				window.open( request_url ); 
			});