Author list is not accessible

I can access the author by simply clicking the author name. But when I try to list down all the authors, this page is simply not accessible, Error 404.

Let me clarify a bit, I am able to access this link –
https://www.quoteschart.com/author/rabindranath-tagore/

but I can’t access –
https://www.quoteschart.com/author/

which is supposed to list down all the authors I have created so far. Like this –
https://binarynote.com/demo/quotebank/authors/

I have bought this theme from the above site. Author and tag list are working fine in the demo site. But after installing this theme in my site, I am wondering why those links are not accessible. I also checked the editor and there is a php file named ‘author-list.php’ which will do all the task to show the authors name in a page – “https://www.quoteschart.com/author/”. Any suggestion to fix this will be greatly appreciated. I am a newbie in wordpress. Thanks.