Our platform is able to track people who use your application, not just devices. Because of this, any user who shares the same username or shares any other user credentials will be rolled up into the same user. If your username or your other user credentials are not globally unique across all your users, Kahuna will roll up two entirely separate users into one - which is not what you want. In this case it is best instead to set your NON-UNIQUE credential as an attribute instead.
Have more questions? Submit a request