DIAGNOSIS: The handset has a small internal backup battery to save your settings, but if power is cut for a long time, that battery can drain and it'll factory reset.
FIX: You'll need to reprogram them. It's simple. 1) Move the desk to your desired height using the up/down buttons. 2) Press and hold the number (1, 2, 3, or 4) you want to assign until the display blinks. That's it. The desk will usually beep to confirm. Repeat for each preset. Your sit/stand reminder timer will also need to be set again via the menu.
IF THAT DIDN'T WORK: If the handset itself is behaving erratically or won't save settings even after reprogramming, the handset might be faulty. Unplug the cable from the control box and reseat it firmly. If problems persist, Uplift can send a new handset.
HEADS UP: For future power outages, consider plugging the desk into a basic surge protector. It won't save the settings forever, but it'll smooth out any minor surges that could cause issues.