What is wrong with this script?

The first texture is there for 30 sec for 30 sec songs and after that it will be back to sparkle for 30 sec again and then the other decal again. I also want the music to stop at the same time as the particles and come witha new particles at the same time. So when the taco song comes the taco particle will come too. But when I tested it, it didn't work. Here is the script:

local decal = game.Workspace.Part.ParticleEmitter

while true do	
	decal.Texture.ULR = ("http://www.roblox.com/asset/?id=186290703")
	Sound.ID = ("http://www.roblox.com/asset/?id=RAININGTACOSONGID")
	wait(30)
	decal.Texture.ULR = ("rbxasset://textures/particles/sparkles_main.dds")
	Sound.ID = ("http://www.roblox.com/asset/?id=SONGID")
	wait(30)
end

Hope you understand! :D

I see your mistake you had decal.Texture.URLAll you need to do is Remove The URL part, Script:

local decal = game.Workspace.Part.ParticleEmitter

while true do   
    decal.Texture= ("http://www.roblox.com/asset/?id=186290703")
    Sound.ID = ("http://www.roblox.com/asset/?id=RAININGTACOSONGID")
    wait(30)
    decal.Texture = ("rbxasset://textures/particles/sparkles_main.dds")
    Sound.ID = ("http://www.roblox.com/asset/?id=SONGID")
    wait(30)
end