What if the magnets came out of the rings? How can I put them back in correctly?
Answer: The + side of the ring repels the + side of the other ring. So you just put the + sides of the 2 rings together, and they should push apart from each other.

These 2 rings should push each other away.
The + side of the ring also should repel away the + side of the foot brace. So all you have to do is put the magnets back into the rings so that + side repels away + side. The side that has nothing should also repel away the side that has nothing.
The + side of one ring attracts to the nothing side of the other ring.
Then glue the rings back in with rubber glue.