Profile has been flagged
If your profile has been flagged you most likely will want to create a Rewards Support Ticket at https://support.brave.com/hc/en-us/requests/new?ticket_form_id=360001302431 so Brave can investigate and decide if they would like to reinstate your account.
For those asking why, there’s clear answer you’ll be given. What can be said is found at Why do profiles get flagged?
NOTE
As of June 2023, being flagged will mean all connected devices are flagged. This no longer will be impacting individual profiles and instead will extend to all devices connected to the same custodial account. These changes are happening because people were trying to circumvent antifraud by simply creating new profiles or attaching new devices. So these changes are coming to prevent that.