Having trouble creating a sprite

[mitterdoo]

So I'm trying to create some effects for my upcoming addon, but there is a problem I'm having with that. If there is an entity behind it, the sprite doesn't render and the entity renders over the sprite. I tried using a sprite that rendered correctly, but it caused the same problem. I am calling render.DrawSprite() in ENT:Draw(). Here is the code that creates the materials to be rendered later:
[lua]
local tglow=CreateMaterial("glow3", "UnlitGeneric", {["$basetexture"] = "sprites/redglow2", ["$spriterendermode"] = 9, ["$additive"] = 1, ["$vertexcolor"] = 1, ["$vertexalpha"] = 1})
local tflash=CreateMaterial("glow1", "UnlitGeneric", {["$basetexture"] = "sprites/light_glow02", ["$spriterendermode"] = 9, ["$additive"] = 1, ["$vertexcolor"] = 1, ["$vertexalpha"] = 1})
[/lua]

I don't know why this is happening and I need help.

[mitterdoo]

Bump.