Ошибка скрипта: bad argument #2 to 'format' (number expected, got string) stack traceback: [C]: in function 'format'?

function SampEvents.onServerMessage(color, msg)
        if msg:find('Вы можете взять %d+ материалов.') and not sampIsChatInputActive() then
            sampSendChat(string.format('/get guns %d', msg))
        end
    end

[ML] (error) main.lua: D:\Games\SAMP\moonloader\main.lua:34: bad argument #2 to 'format' (number expected, got string)
    stack traceback:
        [C]: in function 'format'
        D:\Games\SAMP\moonloader\main.lua:34: in function 'callback'
        D:\Games\SAMP\moonloader\lib\samp\events\core.lua:80: in function <D:\Games\SAMP\moonloader\lib\samp\events\core.lua:54>
    [ML] (error) main.lua: Script died due to error. (1E3671AC)