Hey @PsiclonexD! Welcome to the forums!
So you need to make what you have as “300” into a variable!
I suggest “MaxHealth”. Then you do “Health/Maxhealth” to get your %! Because the bar you’re using is 0-1 in decimals, since the health level is over 300, it’s over 1x the max and so it won’t move until dropping below 300 