Lua Npc buy with backpack

[-vG]

Hello people,
when buying rune pack he buys only 20
each packet being 100 runes how can I fix it?

TFS 0.3.7
version 8.60

lib -> npc.lua

function doNpcSellItem(cid, itemid, amount, subType, ignoreCap, inBackpacks, backpack)
    local amount, subType, ignoreCap, inBackpacks, backpack  = amount or 1, subType or 0, ignoreCap or false, inBackpacks or false, backpack or 1988

    local exhaustionInSeconds = 1
    local storage = 45814
    if(exhaustion.check(cid, storage) == true) then
        doPlayerSendTextMessage(cid, MESSAGE_STATUS_CONSOLE_BLUE, "You cant buy it so fast.")
        return 0
    end
    exhaustion.set(cid, storage, exhaustionInSeconds)

    local ignoreCap = false
    local item, a = nil, 0
    if(inBackpacks) then
        local custom, stackable = 1, isItemStackable(itemid)
        if(stackable) then
            custom = math.max(1, subType)
            subType = amount
            amount = math.max(1, math.floor(amount / 100))
        end

        local container, b = doCreateItemEx(backpack, 1), 1
        for i = 1, amount * custom do
            item = doAddContainerItem(container, itemid, subType)
            if(itemid == ITEM_PARCEL) then
                doAddContainerItem(item, ITEM_LABEL)
            end

            if(isInArray({(getContainerCapById(backpack) * b), amount}, i)) then
                if(doPlayerAddItemEx(cid, container, ignoreCap) ~= RETURNVALUE_NOERROR) then
                    b = b - 1
                    break
                end

                a = i
                if(amount > i) then
                    container = doCreateItemEx(backpack, 1)
                    b = b + 1
                end
            end
        end

        if(not stackable) then
            return a, b
        end

        return (a * subType / custom), b
    end

    if(isItemStackable(itemid)) then
        a = amount * math.max(1, subType)
        repeat
            local tmp = math.min(100, a)
            item = doCreateItemEx(itemid, tmp)
            if(doPlayerAddItemEx(cid, item, ignoreCap) ~= RETURNVALUE_NOERROR) then
                return 0, 0
            end

            a = a - tmp
        until a == 0
        return amount, 0
    end

    for i = 1, amount do
        item = doCreateItemEx(itemid, subType)
        if(itemid == ITEM_PARCEL) then
            doAddContainerItem(item, ITEM_LABEL)
        end

        if(doPlayerAddItemEx(cid, item, ignoreCap) ~= RETURNVALUE_NOERROR) then
            break
        end

        a = i
    end

    return a, 0
end

 

[-vG]

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