from my experience with the new input system is that you need to be careful about how you set it up because is meant to be flexible and have different behaviors while using the same inputs.
so if you are in the menu wasd do something in game they do something else. stuff like that.
so if in game the inputs don’t work, assuming you have studied the manual and read the documentation and set everything right, then it may be that the input is on the wrong set of rule (it thinks the Menu mode is on but you are actually in Game) so check how can you switch those modes