Issue mapping texture to imported quad

Hi there,

I am working on a 3D game with a retro style that requires a lot of billboards. The problem I have is that the standard planes in Unity have way more vertices and surfaces than I need... I just want to map sprites to a simple two triangle quad.

I have imported quads in various formats but every time I try to map my texture, it only maps a portion of it to the quad, resulting in the quad just being one colour, instead of the whole texture being drawn... my textures work with the larger Unity planes.... what would be causing this?

Thanks in advance!