BuddyBoss Platform has a feature to add more fields on the registration page using Profile Fields. Another feature is Profile Types, which allows site admins to choose which members with certain profile types can access the profile fields created.

With the information above, it is commonly set up, where we are expecting to be able to see all the fields in the Registration page but has the Profile Type configured.

To resolve this, make sure that when setting up the Profile Field with Profile Type, ensure that "Users with no profile type" is checked as this will allow it to visibly show on the registration page:

Video Demonstration: 
https://www.loom.com/share/1a6a9ec9429b42f0abb5b6f267edd3e0