@toughhero44417, sorry to hear about the trouble. Ensure that the SD card isn't inserted between the SD card slot and the battery. Doing so can put pressure on the back of the touch display.
If this isn't the case and the rear LCD touch screen display on your HERO5 Black still appears blank, you can try to perform a manual update. Follow the manual update instructions specified on this article: Software Update Instructions for HERO5 Black
Let us know how it works for you.