New Input System Vector2 Throws Error

I have set up a player controller in a 2D project using the new Input System. For the movement, I use a 2D Vector Composite bound to the WASD keys. I also have the same composite bound to the Gamepad Left Stick, Gamepad D-Pad, and the keyboard arrow keys.

It works fine, but when I press a button for both axis (for example, W and A), I get the following error:

Control start index out of range on composite
UnityEngine.InputSystem.LowLevel.<>c__DisplayClass7_0:<set_onUpdate>b__0(NativeInputUpdateType, NativeInputEventBuffer*)
UnityEngineInternal.Input.NativeInputSystem:NotifyUpdate(NativeInputUpdateType, IntPtr) (at C:/buildslave/unity/build/Modules/Input/Private/Input.cs:120)

Any idea what is causing it and how to fix it?

For some reason, regenerating the C# class from the Input Actions asset fixed the problem.