Sorry for the late response. The boxes in your first page are not done according to instructions. Perhaps I was a bit unclear with my wording, and if that was the case I apologize. What I meant was that all of the boxes of page one should have been with all three vanishing points for each one inside the page and if you felt you needed it, you could place explicitly with a mark the vps for the first 3. You boxes should have looked like some variation of this: https://imgur.com/a/2NY6Qdi

Your first 3 boxes by contrast have just one vp relatively close to the boxes, while the other 2 are well outside the page, so much outside that the lines look actually parallel. In your other boxes the perspective you used is always very shallow, resulting in boxes that look almost more isometric than in perspective, and some recurring problems like diverging lines do show up here again.

The reason why I insisted that your first page should consist only of boxes with very visible convergence is that with these kind of viewing angles you can get a much clearer idea of what's happening to parallel lines when you look at them from an angle because you can actually see on the page where are they converging. Once your visual memory has some experience with these cases, more complicated ones, like boxes with far away vps, will naturally be easier than before.

I don't want you to burden much more with other exercises, so I will ask you just one last page of 6 boxes before I will mark this lesson as complete. I'd like you to try again to stick to the instructions for the first page I gave you the last time: the boxes should look somewhat like the one in the linked image. Of course you should try to vary shape, viewing angle and distance of the vps, but in any case for each box their 3 vps must be somewhere inside the page.