I changed the post-cat O2 Sensors.
I reset the light. Drove 120km. Stopped filled the tank then drove another 5km then the light turned on.
Could this error be caused the Activated carbon filter which filters the gas tank vent. It's the oldest part of the car. I installed a used on because the original was damaged when I bought the car.
The error doesn't suggest that it has anything to do with it.