How can it be just for God to punish people for sins if He is in control of everything and it is He who makes them commit sins?

Look at it this way:-

There are 2 levels to knowledge of reality. One is the knowledge you and I can have of reality. The other is the absolute knowledge that only God can have.

We have to operate using the concepts and knowledge we can gain from our experience of reality. To our perceptions we have free will- we are making the decisions. The decisions we make are within the limits set by God (we are not gods and we cannot just change reality to suit us).

For example, I perceive a wall next to me. It seems fairly solid. I perceive that I have a free choice whether or not I put my fist into it. If I choose to do so I would hurt my hand. I could not reasonably blame anyone but myself. No one has been unjust to me. I don't blame God for making the physical laws that lead to my pain.

The same is true for any sin I may commit - its inevitable consequence, in this life or the next, is for me to cause myself harm.

To God's perceptions He is in complete control. But I cannot know in the way that God knows. To enter any debate as if I could is stupid and will only lead to confusion. Some people say "if God has decided that I will do this sin then I cannot escape it." But no one knows what God has decided for you. You do not know your future.