It is working but not in the car. I am also able to shift in automatic mode in AC. In rF2 is all fine. Have you tried a full reset of AC's settings? You can do this by renaming the Assetto Corsa folder in Documents (next time you launch the game it will create a new folder...
Custom auto-clutch and automatic shifting algorithms, plus controller vibration options Highly customizable settings through a UI app Real-time readouts of tire slip and more 📖 Why? There are a number of Gamepad FX scripts for Assetto Corsa out there that target the same issues with controller...