Did you follow it? Like, did you do the 'currently reading' thing? If so just go there and press already read and you should not get notifications of it, or go there and press delete.
It's next to the editing button for weather your reading, already read and currently reading ad it will take it off of the list. I hope that this makes sense.
Once you’ve already rated , go to the manga’s page and under its title cover is the “edit” button. Select it and if the ‘reading’ or ‘read’ option is selected, you can unselect the “subscribe “ button.
Every title is automatically added to you subscriptions for update notifications when you add them to your read or reading list. Make sure to unselect this option at the time of adding them.
So like I don't want a manga that I rated one star to be on my reading list and keep popping up in my notifications, how should I go about this?