Treasure Hunter project Issue with green squares

On the treasure hunter project I can’t get the green tiles to load onto the screen in a gird. The code works because when I use the gold sprite it does but when I use the green tile sprite named blank it just shows up with the black squares. I copied the image link and it’s the right image. I even copied and pasted in the solution code into the project and it still doesn’t work. Can someone Please help me?

Here is the code:

for (let x = 46; x < 437; x += 78) {

    for (let y = 46; y < 437; y += 78) {

      plot = this.add.sprite(x, y, 'blank');

      grid.push(plot)

    }

  };

It works fine when I type in ‘gold’ but not with the blank.