I can't scale the size of UV texture image

I was making this tile following a tutorial. I was usually able to scale UV texture simply in the UV editor screen. However this time, although I did the scaling as I wanted the tiles to appear bigger and larger, it looks exactly the same, very dense. How can I fix it? Thank you so much!

Looks like you have 2 UV sets. So to use one of them put UV map node in material, and select right one:
Then, connect UV map node to textures: