It sounds as if you have likely learned the concepts but not how to apply them.
So, as you suggested, something hasn't clicked.
It's likely that a major issue is the way you've been practicing.
Overall, you've used two solid resources without hitting your score goal. So, there's likely something about how you are using the resources that's not working, and it's also likely that, if you use another resource in the same way, you'll get the same result.
What were your section scores on that last GMAT?
How much time do you typically spend on a practice question?
The good news is that, by adjusting your conception of the GMAT and how you have been preparing for it, you'll hit your score goal.