I had the chance to ask my SA about this since I thought I encountered an issue. Turns out it's Mini's safety feature. You need to press the brake pedal before starting the car. This prevents children from accidentally starting the vehicle and driving away.
I'm looking for one as well as mine didn't have a rear mat also. I'm looking into this but I'm not sure. Anyone here have this mat? https://www.smartliner-usa.com/products/smartliner-custom-fit-for-2022-2023-mini-cooper-se-electric-models
This automatic safety feature can completely stop your car, but it won't stay active indefinitely. After a five-second pause, the system deactivates itself, and you can resume driving by simply pressing the gas pedal.