use coreUserId

app/controllers/user.js

@@ -64,7 +64,7 @@ class UserController extends SiteController {
     router.param('coreUserId', this.populateCoreUser.bind(this));
 
     router.post(
-      '/core/:userId/settings',
+      '/core/:coreUserId/settings',
       limiterService.create(limiterService.config.user.postUpdateCoreSettings),
       checkProfileOwner,
       upload.none(),