Can't join 'User' to association named 'users_roles'; perhaps you misspelled it?

[konami99]

Rails 6.0.6.1
Rolify 6.0.1

Migration has run, so users, users_roles and roles tables have been created

u = User.create name: 'john'
u.add_role :admin
User.includes(:users_roles).first # returns Can't join 'User' to association named 'users_roles' error; but worked fine on Rails 5.2