@JEFFJW9BB You can always start LAYER command then turn ON the layers that LAYISO turned off.
LAYERP command can also help if you made no other layer settings changes since starting LAYISO command.

Ensuring your AutoCAD for MAC variant is fully updated would be the first thing to check: FWIW that never happens ever on it's own, you are expected to go hunt down the latest update file yourself then install it.