Since May of this year I’ve received the following message:
Unfortunately, your Brave Rewards profile has been flagged, and you’re not able to verify with a custodian at this time. This flag can sometimes be due to irregular Brave Ads activity, though it can also be a false positive.
Note that while your Brave Rewards profile is flagged, you won’t be able to verify.
No action is required on your part. Your Brave Rewards profile will be automatically re-evaluated on a regular basis to determine when (or if) the flag can be removed. Please try again every so often to see if the flag has been removed.