How do I cause the script to keep repeating once one sequence is done?

Put the whole script inside a while loop*? .3.

What I would do is put that whole script as a function which will make it when you call the function out it will run the script until the function is over. When the round is over you can then make it where it runs the function.

wait(10)
dft = {} 
local plrs = #game:GetService('Players'):GetChildren()
Debounce = true
local seek = game.Lighting.AzureSword:Clone()
while true do
function GetPlayers()
    local c = game.Players:GetChildren() 
    for i = 1, #c do 
        table.insert(dft, c[i].Name) 
    end 
end

function Start()
if plrs >= 1 then
function Randomize()
    GetPlayers()
    local d = math.random(1, #dft) 
    local s = d 
    local m = Instance.new("Message", game.Workspace) 
    m.Text = "The seeker is ... "..dft[s].."!" 
    wait(1) 
    m:Remove()
    local rndm = game.Players:FindFirstChild(dft[s])

if Debounce then
  for index, plr in pairs(game.Players:GetPlayers()) do
          local char = plr.Character or plr.CharacterAdded:wait() -- Get the character of the player

            local HRP = char:WaitForChild('HumanoidRootPart') -- Wait For the HumanoidRootPart
            HRP.CFrame = CFrame.new(170,1,131) -- CHange the XYZ with the position or use script.Parent.CFrame for example


end
end

  if (rndm ~= nil) then 
        local Player = rndm.Character
        Player:MoveTo(Vector3.new(238, 0.05, -1427))






if (rndm ~= nil) then 
    wait(20) 
      local Player = rndm.Character
        Player:MoveTo(Vector3.new(170,1,131))
seek.Parent = rndm.Backpack
            seek.Character.HumanoidRootPart.CFrame = rndm
end




end


    end
end

while wait(10) do    
    print("Done waiting.")
        print("Randomizing.")
        Randomize()
break
    end


else
    local h = Instance.new("Message")
h.Parent = workspace 
h.Text = "Not enough players."
wait(10)
h:Remove()
end



    plrs = #game:GetService('Players'):GetChildren()
wait(10)
p = game.Players:GetChildren()
for i = 1,#p do
p[i].Character.Head:remove()
end




 local h = Instance.new("Message")
h.Parent = workspace 
h.Text = "Restarting game"
wait(10)
Start()
h:Remove()

I dont expect this to work because I did this right on the browser (I dont have studio with me right now) but it should go around those lines. If you need help I can try to get access to studio and help out. Sorry If I wasn't a help