here you have 2 times localPlayer.
so try:
------------------
function openInventory(Element)
if (pElement) then
if (showInventory) then
showLeft = false
else
showInventory = true
showLeft = true
end
triggerServerEvent("getElementItems", localPlayer, pElement, 2)
activeSide = "bag"
if getElementType(pElement) == "vehicle" then
vehBoot = pElement
if not getElementData(pElement, "veh >> bootOpened") then
triggerServerEvent("toggleTrunk",localPlayer,pElement,1)
setElementData(pElement, "veh >> bootOpened", true)
end
end
end
end
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And dont forget about addEventHandler