DIAGNOSIS The control panel has likely locked up or a thin film of moisture or residue is interfering with the capacitive touch sensors. It's a soft reset situation.
FIX Unplug the blender from the wall outlet. Not just turning it off, but physically disconnect the power cord. Wait a full 60 seconds—this lets any residual power drain from the circuit board. While it's unplugged, take a clean, dry microfiber cloth and gently wipe the entire touchscreen surface. Plug the unit back in. The screen should do a quick light-up sequence. Try pressing the 'Power' button once to wake it up, then test a function.
IF THAT DIDN'T WORK If it's still dead to the touch, there's a chance the ribbon cable connecting the control panel to the main board came loose internally. This isn't a user-serviceable fix. You'd need to contact Ninja customer support, as the base would require opening, which voids the warranty if you do it yourself.
HEADS UP Avoid using wet hands or spraying cleaners directly onto the touchscreen. Always apply cleaner to your cloth first. A persistent unresponsive screen, especially after a reset, points to an internal electronics failure.