DIAGNOSIS: This is almost always a power issue. The control box isn't getting any juice, so the motors won't engage and the display stays dead.
FIX: First, let's trace the power path. 1) Check that the power outlet is working by plugging something else into it. 2) Follow the thick black cable from the control box back to the wall plug. Make sure every connection is fully seated—the one into the wall plug brick, the one into the control box itself, and the one from the control box to the handset. Unplug and firmly reconnect each one.
IF THAT DIDN'T WORK: The internal fuse in the control box might have blown, which can happen from a power surge. You'll need to contact Uplift support; they can send you a replacement control box. It's a straightforward swap, just unplug all the motor and handset cables from the old one and plug them into the new one.
HEADS UP: Never try to force the desk to move manually when it's powered off. You can damage the motor internals or the gear system.