C++ help me understand about recvbyte?

[darkmu]

I am currently using the OTG Premium Version, the Prey Wildcart system has not been implemented and I am trying to implement it, however I am having a hard time understanding about these bytes, here's what I'm analyzing.

Using OTG 1.3 Premium Version with client 12.40

Modules.xml

 <!-- Prey System -->
    <module type="recvbyte" byte="235" script="prey_system/prey.lua" />
    <module type="recvbyte" byte="237" script="prey_system/prey.lua" />

Callback:

player:preyAction(msg)

Data msg:

userdata: 0x04707c58

Function

    local slot = msg:getByte()  
    local action = msg:getByte()
    print(slot)
    if not slot then
        return self:sendErrorDialog("Sorry, there was an issue, please relog-in.")
    end

    -- Verify whether the slot is unlocked
    --print(self:getPreyUnlocked(slot))
    if (self:getPreyUnlocked(slot) ~= 2) then
        return self:sendErrorDialog("Sorry, you don't have this slot unlocked yet.")
    end

Source

int LuaScriptInterface::luaPlayerGetPreyUnlocked(lua_State* L)
{
    // player:getPreyUnlocked(slot)
    Player* player = getUserdata<Player>(L, 1);
    uint16_t slot = getNumber<uint16_t>(L, 2);
    std::cout << slot << std::endl;
    if (player) {
        lua_pushnumber(L, player->getPreyUnlocked(slot));
    }
    else {
        lua_pushnil(L);
    }
    return 1;
}

0 (ZERO) is always returning me, why?