Quick question y'all.

Today I went to go take emissions and the car failed.

2 active codes, p0420 and p0430.

Those both relate to rear 02 sensor efficiency, which is prolly due to the high flow cats.
What is the easiest way to rectify this? I rarely lug the car around.

Of more concern is why my check engine light is not on. Is it possible that someone disabled the bulb in the dash, or does the bulb commonly burn out?

Car is an 08.

Thanks