Diagnosis
The control panel has lost power or is in a locked state. This is distinct from a general power failure if the unit is plugged in.
How to Fix It
Perform a hard reset. Unplug the blender from the wall outlet for a full 60 seconds. While unplugged, press and hold the power button on the front panel for 10 seconds. Reconnect power. The screen should initialize.
If That Didn't Work
Check the power connection at the blender base. The proprietary power brick connector must be fully seated. Try a different, known-working electrical outlet on a separate circuit.
Heads Up
Using the blender on the same circuit as a high-draw appliance like a microwave can cause a voltage drop that may freeze the touchscreen controls.