Lua getThingFromPos TILE NOT FOUT

[LucasFerraz]

function getTopItem(p)
    p.stackpos = 0
    local v = getThingFromPos(p)
    repeat
        p.stackpos = p.stackpos + 1
        v = getThingFromPos(p)
    until v.itemid == 0
    p.stackpos = p.stackpos - 1
    return getThingFromPos(p)
end

It is spamming TILE NOT FOUT. Can someone help to solve it? I've been retired from 'this world' for a long and I am back :3