Expected 'then' when parsing if statement, got <eof>?

Hi, my code keeps getting this error message. I've tried adjusting the 'end's, rewriting the code and looking at multiple different forums to find other solutions. These having not worked. , I'm really lost. Any help/clues or criticism is appreciated.

local part = script.Parent;
local Players = game:GetService("Players");
local screen = script.Parent.Parent.Screen
local SurfaceLight = screen.SurfaceLight
local part = script.Parent

part.Touched:Connect(function(hit)
    local humanoid = hit.Parent:FindFirstChildOfClass("Humanoid");
    if humanoid then
        local player = Players:GetPlayerFromCharacter(hit.Parent);
        screen.Material = Enum.Material.Neon
        SurfaceLight.Enabled = true
    end

part.TouchEnded:Connect(function(hit)
    local humanoid = hit.Parent:FindFirstChildOfClass("Humanoid");
    if humanoid then
        local player = Players:GetPlayerFromCharacter(hit.Parent);
        if part.Touched:Connect(function(hit)
                wait(2)
                    if part.Touched:Connect(function(hit)
                            screen.Material = Enum.Material.Neon
                            SurfaceLight.Enabled = true
                    end) then
                    elseif part.Touched:Connect(function(hit)
                            screen.Material = Enum.Material.SmoothPlastic
                            SurfaceLight.Enabled = false                            
                        end) then

                    end
end)