DIAGNOSIS Probably not the screen itself. This is almost always a loose internal ribbon cable connection, jostled during shipping or a move, or damaged by heat cycles and vibration.
FIX Unplug the unit. Give the top control panel a few firm but careful taps with the heel of your hand. Sometimes this can reseat a loose connection temporarily. If that changes the display, you’ve confirmed it’s a connection issue.
IF THAT DIDN'T WORK The fix requires opening the housing to access the main control board and reseating the display ribbon cable. This voids your warranty and involves electrical components, so it’s not recommended unless you’re experienced. The practical solution is to contact Ninja support for a warranty claim or repair.
HEADS UP Don’t try to use it with a flickering display. The controls might not register correctly, leading to unexpected heating or timer issues.