The error message "Name can't be blank, Surname can't be blank" usually occurs when the user profile has not been created yet in Datamolino.

Please create your Datamolino account using this link: https://app.datamolino.com/auth/users/sign_up.

TIP: Datamolino remembers the invitation in the background, so as soon as the user logs into Datamolino for the first time, the folders that the user was invited into will be shown in the main dashboard.