If your FLEX turns off on its own:

The FLEX has an option to use a timer. Do you have the 2-hour, 4-hour, or 12-hour option selected?

How to use the timer:

1. Ensure the LOCK button is not being used. If it is, press and hold the lock button for 3 seconds to unlock the control panel.
2. Press TIMER to have the air purifier run for a set number of hours (either two, four, or twelve) before turning off. Once one of the three options are selected the light below the selected hour will appear.

Note: If none of the preset hours are selected, the purifier will continue to run until you manually turn it off.

If the lock and timer don't solve the issue, perform the following steps:

1. Unplug the purifier from the wall outlet.
2. Remove the panel and the filter from the purifier.
3. Let the purifier rest for 30 seconds without the filter or panel installed.
4. Reinstall the filter, making sure that it is placed securely back in the unit (insert bottom of the filter first, and then press the top in until it clicks. Then proceed to press on all four corners to ensure that it is completely locked in place.)
5. Place the panel back on the unit, making sure it closes tightly.
6. Plug the purifier back into the wall.
7. Press the power button to power on the purifier.