CakePHP 3 Nested Resources Not Working Properly -

apologies rather vague title, i'm not sure how else describe problem i'm having.

i have 'admin' prefix route configured, , within prefix want set nested resources. have following set up:

groups hasmany users users hasmany items items hasmany comments 

i want urls reflect relationship between groups, users, items, comments, etc. instance, here example urls:

/admin/groups (list groups) /admin/groups/1 (view group id 1) /admin/groups/1/users (list users group id 1) /admin/groups/1/users/12 (view user id 12 group id 1) /admin/groups/1/users/12/items (list items belonging user id 12) ...you idea. 

here relevant part of routes.php file:

router::scope('/', function ($routes) {      $routes->prefix('admin', function ($routes) {          $routes->resources('groups', function ($routes) {             $routes->resources('users', function ($routes) {                 $routes->resources('items', function ($routes) {                     $routes->fallbacks('inflectedroute');                 });                 $routes->fallbacks('inflectedroute');             });             $routes->fallbacks('inflectedroute');         });         $routes->fallbacks('inflectedroute');     });      $routes->fallbacks('inflectedroute'); }); 

according documentation, should automatically create routes ones want, , degree does. instance, going /admin/groups/ call index() function of groupscontroller.php, , /admin/groups/1 call view($id) function. /admin/groups/1/users work (it calls index() function of userscontroller.php). however, that's far goes.

if go /admin/groups/1/users/1, following error message:

 action 1 not defined in userscontroller   error: create userscontroller::1() in file: src/controller/admin/userscontroller.php. 

it seems nesting works degree, not far i'd expect, , not far documentation says will.

any appreciated.