Help me fix this Photoshop line too bug

All right, let's see if anybody can help me with this technical problem. I'm using Photoshop, the newest version on the Big Sur operating system. On a Mac, I've selected the line tool and now I'm going to draw a line. So far, so good. It's exactly what it was supposed to do. Settings are correct. I've got a line selected its shape. It's got a black fill, a black stroke. I've double checked nine points. You've got your weight, your height. All good, right? Except the moment I deselect, it disappears. It's still here. It's, you know, it exists in the background, but it's not a case of bringing it forward. So it's not behind this layer. It just doesn't like to show. Now, if you think that you know what the problem is that it's behind there, look at this. I'll pick a different shape from the same tool set. I'll go here and I'll draw that shape. Now I'll deselect it and see if it disappears. Nope. Whatever this problem is is limited to the line tool. So if anybody can solve this for me, please let me know. Obviously, I've done all the rebooting and reloading software stuff, the obvious stuff, but if anybody can figure this out, there's no documentation or anything I can find online to suggest a solution.