Landscape Material Issue

I am new to unreal and just started with the landscaping. I really wanted to use this instanced material as a layer, and I read online that you could copy the parent into a material function blueprint and use that for the blend. I tried it, but the material stretches across the landscape. I know the material works since when I put it on a cube it looks fine, so I don’t know what the problem is. pls help

Thanks for the reply, I don’t think the Transform Tangent to Vertex was the problem, however your reasoning helped me figure something out. I was able to make it work by adding a landscape layer coordinates and severing the blue masks in one of my material functions.