Tileset issue: Bigger tilesets don't fit/position properly

Hi,
I’m facing an issue where my tileset has bigger tiles in a smaller grid (obligatory).
And no, I can’t change the default 16x16 grid, as I do have active 16x16 tiles.


The orange is a default 16x16, but I need it to extend to the entire tile.

I’m guessing this is an easy fix?

Hi, bumping this for a reply. Sorry.