The social security system has a difficult system to notify changes of circumstances. The total benefits goes upside down if someone does this. That's why lot's of people don't notify benefit system of their little change of circumstances. For example, due to my chronic sickness, I had to leave job and update the benefit system with submitting relevant docs. But after few months, I have realised that the social security system didn't update my benefits and still getting less money where I should get more. It has sorted after submitting further docs and liaising with them a few times which is a nightmare.