Free choice is all through out the Bible.
Except we are not talking about free choices, the ability to choose. People are free to make choices all day long, and most of us do so.
We are talking about the bondage of the will. The lost man is only able to make choices that are within his moral/spiritual nature.
For instance. A fly, one of the simplest of creatures, can walk on the ceiling. But I, a much more complex creature, cannot. Why not? Is the fly better than me? Is the fly smarter than me? (Shut up, Hank!) Why can the fly walk on the ceiling and I can't? Simple. It is not in my physical nature to be able to walk on the ceiling.
The same is true of lost people. They can only do, or choose to do, that which is within their nature.