How can I correct wiring of a half switched receptacle?
You need to join any red wires from the boxes you modified such that the removed red ties into the "other" removed red (or whatever color was used) so that the circuit is carried to the next location.

So if a red wired screw (or so be it, backstab) had another wire on it, or with it, they need to be capped together in the back of the box.