That's very strange Defango. I always upvote your posts. I don't know if it's possible to check who upvote your post and then downvote?

Maybe steemit can change the votingsystem. Once you have voted than you can't undo your vote.

Steemit is getting rich form people like you. Free advertising for them etc.

Keep up the good work bro!

Kind regards,
pariah1972