only dash once in air but infinite dash on ground

Unity Engine
1

it says it all in the title here is the code

if (isGrounded == false && airdash == true && Input.GetKeyDown(KeyCode.Space))
{
dash();
airdash = false;
}
else if (isGrounded == true && airdash == false)
{
airdash = true;
}
else if (isGrounded == true && airdash==false)
{
dash();
}
else if (isGrounded == false && airdash == false)
{

}

it dosent work the only thing that works was the airdash becomes true on air and false when on the ground and when you dash on air

2

your 2nd and 3rd are the same condition also they are not trigered by space

3 
if(Input.GetKeyDown(KeyCode.Space))
{
    if (IsGrounded)
    {
        Dash();
        airdash = true;
        return;
    }    
          
    if(airdash)
    {
        Dash();
        airdash = false;
    }          
}