My guess is that you signed up to the Steem Skillshare curation trail which I believe was a dedicated website. Shitcoiner’s been voting crap for years and was somehow linked to it.

To stop it, go to steemworld.org and check your “account auths”. I’m on my mobile so don’t know the exact location.

Once there, remove whatever auths are currently there and if you do want to autovote - start again.