Check this other recent thread [Stopped playing PS4 to avoid wrecked PS4 HD - #3 by GoldPhoenix0] (Stopped playing PS4 to avoid wrecked PS4 HD - #3 by GoldPhoenix0)
where our friendly neighbourhood console dev, @GoldPhoenix0 has been explaining about game faults versus PS4 system freezes.
If you describe your issue there in perhaps a bit more detail chronologically, they may be able to help you further.