How to Switch colors of an RGB LED with two Piezo-sensor

Still doesn't work..

Yes it does, it works exactly as you have written it. :-

If the green sensor is off the green light is on
If the green sensor is on the green light is off

If the red sensor is off the red light is off
If the red sensor is on the red light is on

If the red sensor is off and the green sensor is off the blue light is on
If the red sensor is on and the green sensor is on the blue light is on

If the red sensor is off and the green sensor is on the blue light is off
If the red sensor is on and the green sensor is off the blue light is off

So that is what it does. Please tell us if it is not doing this, otherwise what do you want it to do?