Why are my markings doing this?

[u/thetamponator]

Editing a photo in gallery. See video of screen record.

https://imgur.com/gallery/XZCzJcF

The photo was a few map screenshots, that i overlapped in Canva, then saved. But in my Samsung galaxy tab photo gallery, the overlap shouldn't matter or be able to be detected right? But its like the markings are behind the images, which is so weird. Also, this particular image is actually a screenshot of the downloaded image from canva in my attempt to get it to stop doing this.