DIAGNOSIS A loose ribbon cable connection between the display PCB and the main logic board. This is an internal wiring fault.
FIX The display is not user-serviceable. You must contact Samsung support for warranty repair or a replacement main unit. Do not attempt to open the sealed handle assembly.
IF THAT DIDN'T WORK The main control board has failed. This requires a full unit replacement under warranty or a professional board swap.
HEADS UP A blank display does not stop the vacuum from working. You can still use it by pressing the power button. You just lose battery and mode indicators.