It is working. Problem is; you are ordering upgrades, which make it more profitable. If the corp sells a lot of products, it's not gonna give it all to you. It's gonna order 2-3 months of supplies and write it off as a business expense. That's why CEOs are always picky about welfare. They pay several taxes that count as a business expense and receive the same profit, but the country receives more from CEO controlled than state.
CEOs want a productive populace that makes the best out of the salaries and is efficient. Their corporations buy(and rumored to) consume less and produce more.
Your state corps aren't a mass commonwealth with you as the focal point. Switch to a common market with a player who doesn't care about profits (like me) who will contract stuff to you at market price to reduce costs. Plus, you can get much higher qua from them. I sell qua 308 to my common market fellows at market price and risk making close to no profit. In the end, I get lots of happy letters and in return, me fellow Union members do the same for me. We all help each-other and make substantial profits to the point where I'm picky about the strategic bombs I buy for no reason.
Common markets with greedy members are useless. They'll pay the minimum, and go for max profits. Markets like The Union's market have members that wanna benefit each-other at the expense of possible profit, leading to actually get us far more than that of the greedy common markets. We communicate a lot, make backroom arms deals, and heck, I'm even producing cargo shuttles for my fellow market members. Do you have fun watching your numbers grow, or your friends? Karma exists in this game.