Problems started once I started to learn Dynamic Subdiv. Ever since I have been turning that on and off a weird bug has arisen: I can’t zoom. i click and rotate, then hold ALT and pan, but when i let go of ALT, zoom does not work. Then rotate doesn’t work - it freezes on one side view. Then hotkeys stop working. I am on a Macbook Pro - 2018.1. any way to fix?