A carport under a bed room is not exactly a wise design. For fire safety reasons and for structural reasons the (most likely) steel reinforced concrete floor/ceiling between carport and home is prone to sound transmission. You might actually share the same steel rods (in the concrete floor) with your neighbours.
In the old western movies one saw the Indian warrior listening at the rail long before the train to be ransacked was in sight.
Building with reeinforced concrete in the domestic sector is still new to most builders/engineers/architects here, so any sound transmission problem is not know of.The responsible engeneer propably never lived in such a building himself and training at university by a lectorer who propably as well never saw the like him/herself - well ....
The only way to go seems the legal route, as Nai has sayed already, and see if there are shortcomings when doing the sound check. This sound check should also consider noises from cars (starting an old diesel jeep at a cold winter morning can create a lot of noise) as well as the banging of doors and boot doors.
If the test fails with the carport -as it is used and designed- then your flat above it is not fit for humane occupation. A solicitor will help you further once the waterproof test results are available.
Good luck.