Try again

-- Client side

local cTimer = { }

function onUserClick ( points, achievements, account )
	local row, col = guiGridListGetSelectedItem ( source )
	if ( row and col and row ~= -1 and col ~= -1 ) then
		local slc = guiGridListGetItemText ( source, row, col )
		local timeSpent = getElementData ( tostring ( slc ), 'timeSpent' )
		for i, v in pairs ( label ) do
			guiSetText ( v, 'Requesting...' )
		end
		guiSetText ( label_account, "Account name: " .. callServerFunction ( 'getAccountName', getPlayerAccount ( slc ) ) or 'N/A' )
		guiSetText ( label_Serial, "Serial: " .. callServerFunction ( 'getPlayerSerial', slc ) or 'Invalid serial' )
		guiSetText ( label_Country, "Country: " .. callServerFunction ( 'exports.admin:getPlayerCountry', slc ) or 'N/A' )
		cTimer [ localPlayer ] = setTimer (
			function ( )
				guiSetText ( label_timespent, "Time online: " .. tostring ( math.floor ( timeSpent / 60 ) ) .. " hours and " .. math.floor ( timeSpent % 60 ) .. " minutes" )
				guiSetText ( label_Ping, "Ping: " .. callServerFunction ( 'getPlayerPing', slc ) )
				guiSetText ( label_achievements, "Achievements Unlocked: " .. getPlayerAchievements ( slc ) )
				guiSetText ( label_points, "NPG Points: " .. getPlayerPoints ( slc ) )
			end,
		50, 0 )
	else
		if ( isTimer ( cTimer [ localPlayer ] ) then
			killTimer ( cTimer [ localPlayer ] )
		end
		guiSetText ( label_account, "Account name: No player selected" )
		guiSetText ( label_Ping, "Ping: No player selected" )
		guiSetText ( label_Serial, "Serial: No player selected" )
		guiSetText ( label_points, "NPG Points: No player selected" )
		guiSetText ( label_timespent, "Time online: No player selected" )
		guiSetText ( label_achievements, "Achievements Unlocked: No player selected" )
		guiSetText ( label_Country, "Country: No player selected" )
	end
end

function callClientFunction(funcname, ...)
    local arg = { ... }
    if (arg[1]) then
        for key, value in next, arg do arg[key] = tonumber(value) or value end
    end
    loadstring("return "..funcname)()(unpack(arg))
end
addEvent("onServerCallsClientFunction", true)
addEventHandler("onServerCallsClientFunction", resourceRoot, callClientFunction)

function callServerFunction(funcname, ...)
    local arg = { ... }
    if (arg[1]) then
        for key, value in next, arg do
            if (type(value) == "number") then arg[key] = tostring(value) end
        end
    end
    triggerServerEvent("onClientCallsServerFunction", resourceRoot , funcname, unpack(arg))
end

-- Server side

function callServerFunction(funcname, ...)
    local arg = { ... }
    if (arg[1]) then
        for key, value in next, arg do arg[key] = tonumber(value) or value end
    end
    loadstring("return "..funcname)()(unpack(arg))
end
addEvent("onClientCallsServerFunction", true)
addEventHandler("onClientCallsServerFunction", resourceRoot , callServerFunction)

function callClientFunction(client, funcname, ...)
    local arg = { ... }
    if (arg[1]) then
        for key, value in next, arg do
            if (type(value) == "number") then arg[key] = tostring(value) end
        end
    end
    triggerClientEvent(client, "onServerCallsClientFunction", resourceRoot, funcname, unpack(arg or {}))
end