Trouble with Single Tile Editor

I’m following along with a 2D platformer tutorial but something isn’t working for me the way it is in the video.

I brought in my sprite sheet, applied paper 2d, created tileset, but when I double click the tileset and it opens the new window, I cannot click on any of the tiles in the Tile Set View to apply the box in the Single Tile Editor.

Not sure if maybe something changed between the version of Unreal I have now and the version that was used when the tutorial was created? Any ideas of what I should try?