Isn't it the case that figures on employment should equal the sum of employees plus the self-employed?
While you didn't share in which direction the equality is off, I would imagine that there is a double-counting issue. If someone is a self-employed person AND a wage earner (e.g. perhaps they have a salaried position but also do freelancing on the side as a registered independent contractor), this may lead to the sum of self-employed workers + wage earners to be higher than Total Employed. That's my thought.