The content is not longer available and will not longer be able again.
Step 1: Wrong URL
User may type the URL incorrectly so, it is ok for the user to check back the URL and make sure it is correct.
Step 2: Application Or Platform Changes
When you have those Content Management System (CMS) like WordPress, Joomla then you may need to remove those plugin or modules.
Step 1: Investigate The Logs
Open the log file, and search for 410 errors, this should at least point you in the direction of where the error is originating from.
Step 2: Unwanted Redirects
If you using Apache web server then you should check your server configuration files as well as the .htaccess file. You can take a search on 410 on the file and if there is a result, then you should check on the redirect rule to make sure what the rule is doing.