I have just been trying to find if this was caused by any third-party app as Safe Mode disabled them. At this stage, I would suggest sending an Error Report attaching the phone logs when that happens to our developers using Samsung Members. You can find this app from Menu> Samsung Members. If this app is not there, download it from the Galaxy Store. Once done, launch it and go to: More (3 dots) > Contact us > Error Reports > Input Symptoms > SEND.