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
 
	-----------------
 
	And dont forget about addEventHandler