почему функция иногда работает иногда нет? вроде все правильно

function Ability01_Filter takes nothing returns boolean
    return GetUnitAbilityLevel(GetFilterUnit(), 'B413') == 0 and IsUnitEnemy(GetFilterUnit(), GetOwningPlayer(GetSpellAbilityUnit())) == false and IsUnitType(GetFilterUnit(),UNIT_TYPE_DEAD) == false and IsUnitType(GetFilterUnit(),UNIT_TYPE_STRUCTURE) == false
endfunction

function Ability01_Timer takes nothing returns nothing
    local timer t = GetExpiredTimer() 
    local integer h = GetHandleId(t) 
    local unit u = LoadUnitHandle(H,h,0)
    local real time = LoadReal(H,h,1)
    local real proverka = LoadReal(H,h,2)
    if GetWidgetLife(u) < .405 and proverka == 0 then
    call UnitRemoveAbility( u, LoadInteger(H, h, 3 ))
    call UnitRemoveAbility( u, LoadInteger(H, h, 4 ))
    set proverka = proverka+1
    call SaveReal(H,h,2,proverka)
    endif
    if time < 0 then
    call UnitRemoveAbility( u, LoadInteger(H, h, 3 ))
    call UnitRemoveAbility( u, LoadInteger(H, h, 4 ))
    call FlushChildHashtable(H, h)
    call PauseTimer(t)
    call DestroyTimer(t)
    else
    call SaveReal(H, h, 1, time - .025)
    endif
    set u = null
    set t = null
endfunction

function Ability01Group takes nothing returns nothing
local timer t = CreateTimer()
local integer h = GetHandleId(t)
local unit u = GetEnumUnit()
local real proverka = 0
local real time = 6
call UnitAddAbility(u,'A535') 
call SetPlayerAbilityAvailable(GetOwningPlayer(u),'A535',false)
call SaveUnitHandle(H,h,0,u)
call SaveReal(H,h,1,time)
call SaveReal(H,h,2,proverka)
call SaveInteger(H,h,3,'A535')
call SaveInteger(H,h,4,'B413')
call TimerStart(t,.025,true,function Ability01_Timer)
set t=null
set u=null
endfunction

function Ability01 takes unit a returns nothing
local group g = CreateGroup()
local boolexpr b = Condition(function Ability01_Filter)
call GroupEnumUnitsInRange(g,GetUnitX(a),GetUnitX(a),900.00,b)
call ForGroup(g,function Ability01Group)
call DestroyBoolExpr(b)
call DestroyGroup(g)
set g=null
set b=null
set a=null
endfunction
//Условие
function AbilityCondition takes nothing returns boolean
local unit u = GetSpellAbilityUnit()
if GetSpellAbilityId() == 'A1ZW' then
call Ability01(u)
endif
set u = null
return false
endfunction