Wordpress - Custom post type single-{custom}.php not working

Visit the permalinks page (which will flush it) and check again. WordPress probably just needs to be nudged to recognize your addition to the hierarchy.

Change the code

From :

 'has_archive'         => true,

To :

 'has_archive'         => false,

And then go to permalink page, change to default and go back to your "pretty permalink"

%postname%/

Now it should work.

The reason why its not going to the single-{custom_post_type}.php page is because of the has_archive. When has_archive is set on true it will look for archive-{custom_post_type}.php instead of the single page.

Hope this worked.