Round Activation does not work when numbers goes above 3?

I wonder why that my script doesn't work when the round should begin. Here's the source of code:

local num = game:GetService("Players")

if num.NumPlayers > 3 then
    return
    end
    workspace.RoundActivationKey.Value = true


if num.NumPlayers < 3 then
    local hint = Instance.new("Hint", workspace)
    hint.Text = "Players not enough. Needs at least 3 players to begin."


while true do wait(1)
    if num.NumPlayers > 3 then
        workspace.RoundActivationKey = true
workspace["CORE OF ROUND - DO NOT DELETE!!! OR WE WILL BE BLOXINGTON BABY!"].Disabled = false --lmao this name is ***
hint:Destroy()
break


end

    end
end  

So basically what I want to do, is to make the round start when the number of players goes above 3, but doesn't work. Someone help? Thanks. -Midnight