In the general settings, I am trying to change the default access rights in the Default User Template, I want to change the default user to "portal user" but when I change the setting, suddenly a pop-up appears with the next message "The user cannot have more than one user type", how can I fix this?

At this point, I only have 2 internal users no more than that, I am new to using the Odoo system.

I want every new user who goes new on the platform to be a portal user

I am using the project Odoo module.

Could somebody around here help me? thanks!!