Can somebody fix this script, of rounds?

This script wont work, it's a round script here it is fix it please:

Maps = {"Wobbly Bridge","Tower Of Magic"}
Time_Per_Round = 60
HowLongMessageLasts = 5
HowLongVotingPeriodLasts = 15
MessageToBeStated = "Seconds Left: "
Option = 1
COLOR = 1
function Op1()
    m = Instance.new("Message", Workspace)
    m.Text = "Map Selected: ".. MAP .."!"
    wait(3)
    m:Destroy()
end
function Op2()
    m = Instance.new("Message", Workspace)
    m.Text = "".. MAP .."____ was picked!"
    wait(3)
    m:Destroy()
end
function Op3()
    m = Instance.new("Message", Workspace)
    m.Text = "You will be playing on the ".. MAP .." map"
    wait(3)
    m:Destroy()
end
function Op4()
    m = Instance.new("Message", Workspace)
    m.Text = ""
    wait(3)
    m:Destroy()
end
Players = game.Players:GetPlayers()
Ls = game.Lighting:GetChildren()
_G.MAPA = {"Wobbly Bridge"}
_G.MAPB = {"Tower Of Magic"}
_G.MAPC = {}
_G.MAPD = {}
_G.MAPE = {}
_G.MAPF = {}
_G.MAPG = {} 
_G.MAPH = {}
_G.MAPI = {}
_G.MAPJ = {}
_G.MAPK = {}
_G.MAPL = {}
_G.MAPM = {}
_G.MAPN = {}
_G.MAPO = {}
_G.MAPP = {}
_G.MAPQ = {}
_G.MAPR = {}
_G.NothingCurrently = {}
Lasting = HowLongVotingPeriodLasts
while true do
    HowLongVotingPeriodLasts = Lasting
    if #Players > 1 then
        for o = 1,#Players do
            gui = game.Lighting.Vote:Clone()
            gui.Parent = Players[o].PlayerGui
        end
        repeat
            a = HowLongVotingPeriodLasts
            wait(1)
            m = Instance.new("Message", Workspace)
            m.Text = "Voting Time: "
            a = a - 1
            wait(1)         
        until a == 0
        m:Destroy()
        for i = 1,#Players do
            val = Players[i].Map.Value
            table.insert(_G[val], val)
        end
            mapn = math.max(#_G.MAPA, #_G.MAPB, #_G.MAPC, #_G.MAPD, #_G.MAPE, #_G.MAPF, #_G.MAPG, #_G.MAPH, #_G.MAPI, #_G.MAPJ, #_G.MAPK, #_G.MAPL, #_G.MAPM, #_G.MAPN, #_G.MAPO, #_G.MAPP, #_G.MAPQ, #_G.MAPR)
            if #_G.MAPA == mapn then
                for u = 1,#Ls do
                    if Ls[u]:FindFirstChild("A") ~= nil then
                        Pick = Ls[u]
                    end
                end
            end
        Mapp = Pick:Clone()
        Mapp.Parent = Workspace
        MAP = Mapp.Name
        if Option == 1 then
            Op1()
        elseif Option == 2 then
            Op2()
        elseif Option == 3 then
            Op3()
        elseif Option == 4 then
            Op4()
        else
            print("Invalid option")
        end
        for y = 1,#Players do
            if COLOR == 1 then
                Players[y].TeamColor = BrickColor.new("Really red")
                COLOR = 2
            elseif COLOR == 2 then
                Players[y].TeamColor = BrickColor.new("Really blue")
                COLOR = 1
            end
        end
    end
end