I'm new to skripting and I am having a little trouble. The variable doesn't seem to change but it gives hearts over the maximum.

Code (Text):

1. on join:
2.     if {joins::*} does not contain player's uuid:
3.         add player's uuid to {joins::*}
4.         set {health::%uuid of player%} to 10
5. on death of player:
6.     if attacker is a player:
7.         if maximum health of attacker <= 200:
8.             if maximum health of victim >= 1:
9.                 add 1 to {health::%uuid of attacker%}
10.                 set the maximum health of attacker to {health::%uuid of attacker%}
11.                 execute console command "/heal %attacker%"
12.                 subtract 1 from {health::%uuid of victim%}
13.                 set the maximum health of victim to {health::%uuid of victim%}
14.             else:
15.                 send "You cant gain hearts from this player"
16.                 stop
17. command /sethearts [<offline player>] [<number>]:
18.     permission: skript.sethearts
19.     trigger:
20.         set {health::%uuid of arg-1%} to arg-2
21.         set the maximum health of arg-1 to {health::%uuid of arg-1%}
22.         message "&6Set %arg-1%'s hearts to %arg-2%"
23. command /resethearts [<offline player>]:
24.     permission: skript.resethearts
25.     trigger:
26.         set {health::%uuid of arg-1%} to 10
27.         set the maximum health of arg-1 to 10
28.         message "&6Reset %arg-1%'s hearts"
29. command /hearts [<offline player>]:
30.     permission: skript.hearts
31.     trigger:
32.         message "&6%arg-1% has %{health::%uuid of arg-1%}% hearts"