Solved script crashes my client

[Matt17]

<action itemid="5941" event="script" value="tiers.lua"/>
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function onUse(cid, item, fromPosition, itemEx, toPosition)
local tiers = {
{tier1 = 2466, tier2 = 2472},
{tier1 = 2470, tier2 = 2647}
}
for i = 1, #tiers do
local tier1 = tiers.tier1
local tier2 = tiers.tier2
if itemEx.itemid == tier1 then
doTransformItem(itemEx.uid, tier2)
doCreatureSay(cid, "TRANSFORM", TALKTYPE_MONSTER_SAY)
doSendMagicEffect(getThingPosition(itemEx.uid), CONST_ME_FIREWORK_RED)
doRemoveItem(item.uid)
end
end
return true
end
anyone know why this crashes my client everytime i upgrade the item.. it upgrades from t1 to t2 but it crashes the client