I started from lvl 1 (wizard) ran rifts with my follower (Templar) just fine. At lvl 50 I decided to do bounties for the Cains set. I completed 2 act bounties and we going for a 3rd when my follower stopped following me. he wouldn’t move from the teleport pad.
I got an enemy (plague skeleton archer) to follow over to the teleport pad (different one) and wanted to see if I could get my Templar to do something. It wasn’t till after the skeleton layed down a poison patch overlapping his feet that I heard a rapid fire sound of clanging swords and the skeleton’s health was going down. My Templar follower never moved though.