I sounds like you already tried this... But here is the official procedure.
For vehicles without steering wheel controls, do the
following:
1. Without pressing the pedals, turn the ignition key to
the on position without starting the engine.
2. Wait five seconds.
3. Completely press the brake and the accelerator
pedals simultaneously and hold for ten seconds.
The system is now reset.
4. Turn the ignition key off.
The next time the engine is started, the message will
no longer be displayed. Always reset the FUEL FILTER
LIFE system after a fuel filter change.