Sandstone Wall texture

I am creating new files for sandstone walls to capture the texture from my smooth sandstone block.

I'm using the following script:

{
"parent": "block/template_wall_side",
"textures": {
"wall": "block/sandstone_smooth"
}
}

and
{
"parent": "block/template_wall_post",
"textures": {
"wall": "block/sandstone_smooth"
}
}

So both Side and Post should capture texture from my smooth sandstone, but I end up with this, Only the upper part of the wall and the posts have new texture but the sides under dont. I thought it had to do with the actual smooth sandstone texture missing a top and a bottom so I added that but it didnt work.
What am i missing? :(