cannot open invoice link

Sorry, the page you are looking for could not be found.

[Wed Feb 26 04:09:54.270949 2020] [autoindex:error] [pid 31837] [client 1.1.1.1:55074] AH01276: Cannot serve directory /home/localhost/domains/ninja.localhost.com/public_html/: No matching DirectoryIndex (index.html,index.htm,index.php,index.php4,index.php5) found, and server-generated directory index forbidden by Options directive

Not sure, maybe this will help?

https://www.invoiceninja.com/forums/topic/index-file-missing/