Lua Spawn box with item inside

[skywalker16]

I created this script and tried several diffrent things, which all did not work. I only found scripts which add bp to players and then items in the bp but not any for a item inside a created box on the map.

Thats my script:

for i = 1, #spawn_item_position do
local box_id = 1738
doCreateItem(box_id, spawn_item_position)
doAddContainerItem(getThingFromPos(spawn_item_position), (spawn_item_id[1]))

Anyone got an idea?