Sell all bug?

[Skuter]

Hello, I'm using TFS 0.3.6 example trader template, but I have problem with sell all while ignore equipped is unchecked
Here is buy/sell part of code

local onBuy = function(cid, item, subType, amount, ignoreCap, inBackpacks)
    if(items[item] == nil) then
        selfSay("Ehm.. sorry... this shouldn't be there, I'm not selling it.", cid)
        return
    end

    if(getPlayerMoney(cid) >= amount * items[item].buyPrice) then
        local itemz, i = doNpcSellItem(cid, item, amount, subType, ignoreCap, inBackpacks)
        if(i < amount) then
            if(i == 0) then
                selfSay("Sorry, but you don't have space to take it.", cid)
            else
                selfSay("I've sold some for you, but it seems you can't carry more than this. I won't take more money than necessary.", cid)
                doPlayerRemoveMoney(cid, i * items[item].buyPrice)
            end
        else
            selfSay("Thanks for the money!", cid)
            doPlayerRemoveMoney(cid, amount * items[item].buyPrice)
        end
    else
        selfSay("Stfu noob, you don't have money.", cid)
    end
end

local onSell = function(cid, item, subType, amount, ignoreCap, inBackpacks)
    if(items[item] == nil) then
        selfSay("Ehm.. sorry... this shouldn't be there, I'm not buying it.", cid)
    end

    if(subType < 1) then
        subType = -1
    end
    if(doPlayerRemoveItem(cid, item, amount, subType)) then
        doPlayerAddMoney(cid, items[item].sellPrice * amount)
        selfSay("Here you are.", cid)
    else
        selfSay("No item, no deal.", cid)
    end
   
end

And the item table:

local itemWindow = {
    {id=1988, subType=0, buy=10, sell=0, name="bagpack"},
    {id=12746, subType=0, buy=10000, sell=0, name="AOL"},
    {id=2265, subType=0, buy=10, sell=0, name="medicine"},
    {id=2273, subType=0, buy=100, sell=0, name="ultimate healing"},
    {id=3366, subType=0, buy=0, sell=10000, name="Magic Plate Armor"}
}

And when I want to sell MPAs it sells whole backpack