Hello, Usually, to reset a samsung unit, press the two upper buttons on each side of the panel, at the same time for more than 8 seconds or until you hear a chime.
Give it a try and let me know what happen. If it did not work, please give me your model number and I will see what I can do more.
Press them while the unit is plugged in .
It worked, thanks! you just saved my groceries.