how to fix this instance not playing music?

Module script

local Regions = workspace.Regions
local module = {
ChangeMusic = function()
for i,v in pairs(Regions:GetChildren()) do 
	v:WaitForChild("Music")
	script.Parent.Sound.SoundId = v.Music
	end
	end
	}
return module

03:08:13.574 - Players.hokyboy.PlayerGui.MusicHandler.MusicModule:6: invalid argument #3 (string expected, got Instance)