2012 Jeep Cherokee limp mode

2012 Jeep Cherokee SRT8 when decelerating from 100km per hour the engine check light comes on, the code is for low oil pressure and the vehicle goes into limp mode and has reduced power, has had a new oil pressure switch and new engine ECU, any ideas

What is the dipstick reading? How often do you chec your oil level?

Have you checked the oil pressure when the engine is running with a mechanical gauge? Confirming the actual oil pressure is basic diagnostics.