for some reason drawings on the top layer wouldn't show when bottom layer has a image imported


I’m drawing over a rough storyboard that’s done on photoshop on Storyboard pro. I imported the rough panels as a layer into the storyboard pro panel
I’m working on, and it is somehow impossible to draw over on a different layers that are top of the image layer.

I can see the over drawn lines once I put the opacity of the bottom image down or shut it down, but otherwise, can’t really see
once I turn the image layer back on.

I’m so confused that this problem appeared all of the sudden…? because It was working just fine about a minute ago. I might have accidentally
clicked on some kind of a random hot keys, but couldn’t find a solution just by googling.

Is there a way I can solve it?

Thank you,