RenderTexture turn my model to black, why ?

I am trying to paint any models, it paints and works fine untill i stop playing.

My RenderTexture turns pitch black as you can see. I cannot figure out what should i do. I want my RenderTexture go back to white.

It gets back to normal after i just save any script. Like add a line and save then it would come back to white. I don’t know why it happens.

So i found a solution for me. I noticed that my Basematerial couldn’t hold the white texture, it releases after i turn off the game. So on next start it stayed black.

Now all i did is set the base material to white onStart. Works for me.
`private void Start()

    brushColor =;
    BrushCursor.GetComponent<SpriteRenderer>().sprite = CursorSprite;

    BaseMaterial.mainTexture = (Texture)Resources.Load("Default-ParticleSystem");