Why is twitter marking my tweets as sensitive material?

As the title says, why is twitter marking my tweets as sensitive ? I already unchecked "Mark media I tweet as containing material that may be sensitive" but still.

Nevermind i got it. I have unchecked that but only takes effect on the next ones

I think you haven't solved the problem, that switch is not good for that. Just wait a few tweets until it's happening again. Twitter has some kind of image recognition in place, which automatically marks those tweets as sensitive, which contain adult pics for instance, however their recognition is far from perfect, so a lot of adult pics slip through, while others aren't.