Custom damage skript no work

[Fwify]

When ever I take damage it registers it as normal damage for a second. Sometimes when it reaches to low enough it kills the player normally even when the custom health I made doesnt reach to 0

on damage:
  set {strengthInput::%attacker%} to damage
  wait 1 tick
  remove {strengthInput::%attacker%} from {health::%uuid of victim%}
  set victim's health to ({health::%uuid of victim%} / ({maxhealth::%uuid of victim%} / 20)) / 2
  if {health::%uuid of victim%} < 0:
    kill the victim
    wait 1 second
    set {health::%uuid of victim%} to {maxhealth::%uuid of victim%}

 

[completeidiot]

try changing {thing::%uuid of victim%} to {thing::%victim's uuid%}