Rear derailleurs have what is known as a B-screw. Its job is to bring the derailleur as close to the cogs as possible. Your largest cog is now a lot smaller, so your derailleur is probably way below where it should be.

Depending on the make of your derailleur, the B-screw is in various places, and some designs make it so tightening the B-screw brings the derailleur closer to the cogs, and some make it so loosening the B-screw bring the derailleur in closer. Post the make / model of your derailleur and somebody can probably give you some specifics.

Chain length can also mess you up a bit. i.e., your chain can probably be made quite a bit shorter now.

Was it shifting fine with the 14-32? The 13-23 is a six-speed cluster as well, right? Do you have the 13-23 fully seated on the hub?