Texture applying to each triangle

When I apply a material to an fbx i’ve imported, It applies to each triangle separately. For example, I imported a square and the texture applies to each of the half triangles. How can I fix this so the texture will apply to the entire square?


Do these triangles have the same material index?

It sounds as though every single tri has been given a uniform UV so that the texture essentially tessellates across the mesh. Checks the UVs.