Looks like it got axed due to the light novel lacking content, looked it up on novelupdates and it only has 190 chapters currently. Seems to me the ln didn't produce enough content and wasn't so well received thus in turn the manga got axed.
Yea the chapters self published chapters for this taken down seem like an overreaction from mangadex I doubt they check and just do sweeping takedowns based on published stuff.
It's fine right dark is one of those mass scanlation groups where they post several chapters then proceed to abruptly drop it. They aim to mass post trending stuff for their website to get views.