How to get rid of background on a user interface material?

Hello,

I made an HP bar inside of a material and brought it into a widget but it has a black background and I don’t know how to get rid of it. The only tutorials I can find on this are how to get rid of a background for a texture. There isn’t a texture making my HP bar. Its made almost entirely in blueprint, and its animated so I don’t know how to get the alpha to get rid of the background.

If anybody can help with this, that would be amazing. I added the photo below showing the black background.