If statement noop :)

I want to make a life sýstem in my game. FX. You have 3 lifes and you die at 0

i tried for a while and came up with this:

when you die Lives() is called to check if you need to die or just loose one life but this code just take all your lives at once. how can i run this if statement once until lives() is called again? Thanks!

public void lives() {

     if (lives > 1)
     {
         lives--;
     } 

else Die()