Deck buttons no longer works after MIDI collision on DDJ-REV7

Before I have read about the instruction saying not to launch multiple DJ software (includes DAWs), I started both FL studio and Serato because I need to record my scratches.
And right after FL studio notifying me about not able to bind the REV7 (which is expected as it's already used by Serato), the entire left deck button dies out and refuse to have any response.

Factory reset and firmware update is tried, pumping MIDI signal into those button is also tried, and still no luck. Any advice on getting it for a true factory reset?