@TeamYouTube why am I still seeing videos in my recommendations if I've blocked the channel? I mean, I blocked it for a reason. What's the point in having the option to block when I still have to see them anyway? 
You can always share your thoughts by submitting a feedback. Here's how: https://yt.be/help/ghA5 . Also, could you try clearing your search & watch history and sign out > sign back in to see if that helps?