InvokeRepeating("MoreTransparency", 0, 0.1f);
InvokeRepeating("LessTransparency", 0, 0.1f);

private void LessTransparency()
{
    if (alphalvl >= 1)
    {
    CancelInvoke("LessTransparency");
    }
    CancelInvoke("MoreTransparency");
    alphalvl = alphalvl + 0.3f;
    ChangeColor();
}
private void MoreTransparency()
{
    if(alphalvl <= 0)
    {
        CancelInvoke("MoreTransparency");
    }
    CancelInvoke("LessTransparency");
    alphalvl = alphalvl - 0.3f;
    ChangeColor();