I got issues trying to teleport all players to one part?

I previously tried to use this but it doesn't work

for i,v in pairs(game.Players:GetPlayers()) do 
    v.Character.HumanoidRootPart.CFrame = CFrame.new(workspace.tp) 
end

I need to be able to teleport all players to a map once its loaded and back when the map is unloaded/round is over but my teleport script doesnt seem two work

while true do
        local map = math.random(1, 4)
                if map == 1 then
                    local gamespawn = game.Lighting.Map1.SpawnLocation
                    local m = Instance.new("Message", game.Workspace)
                    m.Text = "map1test" 
                    wait(3)
                    ------------------------------
--                  Code where all players get teleported into map
                    ------------------------------
                    m:Destroy()
                    local Map1copy = game.Lighting.Map1:clone()
                    Map1copy.Parent = game.Workspace
                    wait(4)
                    ------------------------------
--                  Code where all the players get teleported back to the lobby
                    ------------------------------
                    Map1copy:Destroy()
                elseif map == 2 then
                    local m = Instance.new("Message", game.Workspace)
                    m.Text = "map2test" 
                    wait(3)
                    ------------------------------
--                  Code where all players get teleported into map
                    ------------------------------
                    m:Destroy()
                    local Map2copy = game.Lighting.Map2:clone()
                    Map2copy.Parent = game.Workspace
                    wait(4) 
                    ------------------------------
--                  Code where all the players get teleported back to the lobby
                    ------------------------------
                    Map2copy:Destroy()
                elseif map == 3 then
                    local m = Instance.new("Message", game.Workspace)
                    m.Text = "map3test" 
                    wait(3)
                    ------------------------------
--                  Code where all players get teleported into map
                    ------------------------------
                    m:Destroy()
                    local Map3copy = game.Lighting.Map3:clone()
                    Map3copy.Parent = game.Workspace
                    wait(4) 
                    ------------------------------
--                  Code where all the players get teleported back to the lobby
                    ------------------------------
                    Map3copy:Destroy()
                elseif map == 4 then
                    local m = Instance.new("Message", game.Workspace)
                    m.Text = "map4test" 
                    wait(3)
                    ------------------------------
--                  Code where all players get teleported into map
                    ------------------------------
                    m:Destroy()
                    local Map4copy = game.Lighting.Map4:clone()
                    Map4copy.Parent = game.Workspace
                    wait(4) 
                    ------------------------------
--                  Code where all the players get teleported back to the lobby
                    ------------------------------
                    Map4copy:Destroy()
                end
end