Diagnosis
The desk's control unit has lost its saved settings. A brief power interruption or a voltage spike can cause this.
How to Fix It
You need to reprogram the controller. Unplug the desk for a full 60 seconds. Plug it back in. Do not press any buttons. Let it sit for another minute. Then, set the desk to your desired height manually. Press and hold the 'M' button until it beeps, then press '1' to save. Repeat for other positions.
If That Didn't Work
The control panel itself might be faulty. The membrane switches can wear out. Try pressing the buttons more firmly and directly in the center. If some buttons work and others don't, it's likely the panel.
Heads Up
If you have to reset it more than once a month, plug the desk directly into a wall outlet, not a power strip. Surge protectors can sometimes interfere with the low-voltage logic.