Why isn't this team changer delete'r working?

It did work, though it only checked once. The if will not execute on its own each time.

Using the GetPropertyChangedSignal function we can listen for a specific property change.

local Player = game:GetService("Players").LocalPlayer

Player:GetPropertyChangedSignal("Team"):Connect(function()
    if Player.Team.TeamColor == BrickColor.new("Dark stone grey") then
        print("Prisoner")
        script.Parent:Destroy()
    elseif Player.Team.TeamColor == BrickColor.new("White") then
        print("Civilian")
    end
end)

Basically the code executes each time the team changes and only when the team changes. If you do not know about events already check them out here: events

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