Timcliff replied this to me:
Users are only allowed to have one 'free' account created by Steemit. If you need a new account, you will either need to use a service like AnonSteem or have a friend create the account with SteemConnect.
https://steemit.com/news/@timcliff/new-tool-from-busy-org-create-new-steem-blockchain-accounts-with-steemconnect