Enable Input in C++

Closed, because of duplication:

Hey,
I have following problem:

I want to controll Keyboard/Mouse inputs inside my PlayerController but somehow it doesn’t recognize the keyboard/ mouse inputs.

Inside the PlayerController:

Tick()
{
    if (IsInputKeyDown(EKeys::A))
    ....
    if(WasInputKeyJustPressed(EKeys::A))
    ......

}

II’ve tried to Enable Inputs like this:

PlayerController::BeginPlay()
{
 EnableInout(this);
}

but nothing works.

Can anyone help me?