Help with variables as a head

[GMAN1233]

hello i am trying to create a skyblock skript where you have /island top but am confused because i am not getting a head when using a variable as a placeholder for the head.

skript

if arg-1 is "top":
create a gui with virtual chest inventory with 5 rows named "Island Top":
make gui slot 0,1,2,3,4,5,6,7,8,9,17,18,26,27,35,36,37,38,39,40,41,42,43,44,10,11,12,14,15,16,18,19,20,22,24,25,28,30,31,32,34 with white glass pane named "&f":
cancel event
make gui slot 13 with {head}'s skull:
cancel event
open last gui for the player



command /loop:
trigger:
loop {lvl::*}:
set {_loop::%loop-index%} to loop-index
loop {lvl::*}:
set {_top::%loop-index%} to {lvl::%loop-index%}
set {_playersSorted::*} to sortHighestToLowest({_loop::*}, {_top::*})
set {_num} to 1
loop {_playersSorted::*}:
if {_num} <= 5:
set {topkiller:layer::%loop-index%} to loop-value
set {topkiller::kills::%loop-index%} to {lvl::%loop-value%}
add 1 to {_num}
else:
stop

function sortHighestToLowest(indexes: strings, values: objects) :: strings:
set {_size} to size of {_values::*}
loop {_size} times:
loop {_size} - 1 times:
set {_value1} to {_values::%loop-number-2%}
set {_value2} to {_values::%loop-number-2 + 1%}
{_value1} is less than {_value2}
set {_index1} to {_indexes::%loop-number-2%}
set {_indexes::%loop-number-2%} to {_indexes::%loop-number-2 + 1%}
set {_values::%loop-number-2%} to {_value2}
set {_indexes::%loop-number-2 + 1%} to {_index1}
set {_values::%loop-number-2 + 1%} to {_value1}
remove 1 from {_size}
return {_indexes::*}
set {head} to {topkiller:layer::1}
command /t:
trigger:
send "%{topkiller::kills::1}% %{topkiller:layer::1}%" to player
send "%{topkiller::kills::2}% %{topkiller:layer::2}%" to player
[doublepost=1648853789,1648853754][/doublepost]sorry i dont know how to propperly post a skript