If you haven't authorized anyone, then tell @costas-mick that he can't share your content anywhere else.
Let me explain something: If you share your content, you'll be able to give more visibility to Hive, your work, and your blog (which is awesome). Additionally, you'll be able to receive 100% of the rewards generated by sharing your posts on Reddit.
If someone else shares your content, then you'll only receive 20% of those rewards.
I recommend you activate the F.R.I.D.A.Y. bot on Discord. This bot will notify you immediately when someone else takes your content, and any other movement on your account, which is important, since our account activities are of interest to us.
And too read the tutorial provided above. If you have any questions, you can search for @sirenahippie on Discord; she'll be able to guide you.