Jumping and Gravitation Jscript (statement,side-effect error)

So i am trying to make my character jump with gravitation - and I get the message;

      "Expression in Statement must only be executed for the side-effects" 

I think this means that my code does not DO anything… can somebody help me figure out what is wrong?

var JumpH = 8;
var isFalling = false;
var jumpForce = 10;
var gravitasjon = -15;



function Update () {
	
	if (GameObject.Velocity.y < 0.29);
	{
		rigidbody.AddForce.y * gravitasjon;
	}
}

function FixedUpdate () {

	if (Input.GetKey ("space") && isFalling == false)
	{
		rigidbody.velocity.y = JumpH;
		isFalling = true;
	}
}
	
function OnColissionStay ()
{
	isFalling = false;
}

I also tried adding (… gravitasjon * Time.deltaTime) and nothing… any thoughts?

Am sure the compiler tells you that line 12 has the problem. You conveniently ignored this piece of information. On line 12 you perform a calculation, but don’t do anything with the result. The compiler is telling you that’s pointless.