Ours does this every once in a while but it always comes back after a reboot. It seems to happen whenever there’s a power fluctuation even though it’s on it’s own power supply.
Usually it’s overnight or on a weekend, I’ll come in the following morning to a message that says something like it can’t communicate with the LCD panel. I reboot it and once in a while it comes back with a blank screen. When that happens I unplug it from the power supply, let it sit a minute, then turn it back on. Never had it fail to come back after that.