Lua Movement script error - StepIn StepOut

[lyczos]

local tile = 426 -- tile id
local wall = 1049	-- id of wall to remove
[COLOR="red"]local pos = {x=988, y=805, z=14} [/COLOR]-- position of wall to remove 
local wallFromPos = getThingfromPos(pos) -- get item uid

function onStepIn(cid, item, position, fromPosition, itemEx, toPosition)
	 if isPlayer(cid) then
		doRemoveItem(wallFromPos.uid, 1)
		doPlayerSendTextMessage(cid, MESSAGE_INFO_DESCR, "You have removed the wall.")
		doTransformItem(item.uid, 425)
	
	end 
	return true
end

function onStepOut(cid, item, position, fromPosition, itemEx, toPosition)
	 if isPlayer(cid) then
		doCreateItem(wall, 1, pos)
		doPlayerSendTextMessage(cid, MESSAGE_INFO_DESCR, "Wall is back.")
		doTransformItem(item.uid, 426)
	
	end
	return true 
end

This line (pos) making crash. i tryed without "x", "y", "z" but always is crash...

 

[Cykotitan]

function onStepIn(cid, item, pos, fromPos)
	if isPlayer(cid) then
		doRemoveItem(getTileItemById({x=988, y=805, z=14}, 1049).uid)
		doPlayerSendTextMessage(cid, MESSAGE_INFO_DESCR, 'You have removed the wall.')
		doTransformItem(item.uid, 425)
	end
end

function onStepOut(cid, item, pos, fromPos)
	if isPlayer(cid) then
		doCreateItem(1049, 1, {x=988, y=805, z=14})
		doPlayerSendTextMessage(cid, MESSAGE_INFO_DESCR, 'Wall is back.')
		doTransformItem(item.uid, 426)
	end
end