G11 730i facelift - Coasting and braking downhill still expends gas

[Patty60205]

For context:
I live in Taiwan and we have the 730i, a four cylinder model. I believe this car is only available in certain markets where tax is levied based on engine displacement.

Issue:
Since the purchase of my G11 generation 730i (facelift), I noticed the car will expend gas while coasting downhill. I drive my 730i to work via highway, and the highway has a few downhill sections. The car will continue to expend gas even though the car is coasting faster and faster downhill. I need to brake continuously to prevent forward collision because the car will continue to expend gas DURING AND AFTER braking.

Outside of driving uphill and downhill, expending gas while coasting allows the car ride to feel smoother, however the car shouldn’t need to expend gas when coasting downhill. I am quite sure of this because my pre-facelift G11 generation 730d and my wife's 420i do not have this issue. I also noticed that a quick and sharp stab at the gas pedal makes the car coast without expending gas. Could this issue be caused by a bug/error in the programming logic?

Has anyone encountered anything similar and if so how did you solve this?

PS:
I already reached out to my local dealership for assistance, but they replied this is normal behavior for the car because the dealership's 730i test drive car has the exact same issue when coasting downhill (at the same downhill section of the highway). However, they were unable to provide 740i or above for test drive.

I also reached out to BMW Germany and disappointingly their reply boils down to "This is not my problem."