I’ve run into an issue where WordPress stops using single-posttype.php when I access a post using a custom permalink (domain.com/posttype/slug) I can still see the correct template when I access using domain.com/?posttype=slug.

I’ve tried changing my permalink structure which hasn’t worked and I can’t figure out what setting in register_post_types could cause this issue. Any ideas?

Thanks

register post type function call –

register_post_type( 'posttype',
array(
'labels' => array(
'name' => __( 'Post Types' ),
'singular_name' => __( 'Post type' )
),
'rewrite' => array('slug' => 'posttype'),
'public' => true,
'has_archive' => false,
'description' => 'Menus displayed to customers.',
'supports' => array('title','editor'),
'show_in_nav_menus' => true,
)
);