user_id or device_id to the DoveRunner DRM blacklist in the Multi-DRM service. You can manage the blacklist through the DoveRunner Console under Multi-DRM → Blacklist Management (User Blacklist / Device Blacklist) or by using the Blacklist API.user_id or device_id is added to the blacklist, DoveRunner checks the list for every incoming DRM license request. If the request matches a blacklisted identifier, the license is immediately denied and the user is unable to decrypt or play DRM-protected content, even if they still have a valid playback link or application access.user_id or device_id. If needed, the user can be unblocked later by removing the corresponding identifier from the blacklist, after which DRM license issuance will resume normally.