Role hierarchy not resolving all sub-roles correctly

Hello Everyone
I have created 4 roles in Casdoor
https://demo.casdoor.com/roles
admin
sales
hr
superadmin

Also, i have set sub role of hr, sales as admin, and subrole of superadmin as admin.
Given these conditions, hierarchy should be superadmin > admin > (hr, sales)
So superadmin user ideally should have all the roles but this is not the case, and only sales and superadmin is coming, Am i missing something or this is a potential bug ?

Hey @hsluoyz , Would you be able to check this once, I think this is probable bug in the system.

use casbin permissions if you need hierarchy, it

it's better

point out the bug in code, better come with a PR