Putting pictures side by side on a -New- created background

[Barbara Buffington]

I have a Sierra operating system on my MacBook Pro and followed the tried and true procedure, of placing pictures side by side in a New image background, exactly the way I've done it time and again, but now it doesn't work that way any longer. I attached a screen shot of what appears when I attempt to move images, with my cursor and the 'moving'[attachment=561] icon clicked on, which doesn't work. There are two weird little symbols next to my white cursor that move along with it on the page. One is a tiny serrated black circle with a line through it and the other is a little box that has itsy-bitsy loops all around its inner sides, which makes it look a bit like a picture frame with a white center. The photos won't budge from being piled on top of one another no matter what I do. A total of three pictures are layered over each other, because I can't move them, even though there's more than enough image space on the New white backdrop I created for them...??? Can you, or anyone, figure out what has changed to make this process impossible to perform and the features/functions that worked previously now inoperable? I make comparisons, between similar items, on a regular basis and need to be able to employ the side by side picture technique for that purpose. Please help rectify the problem I'm having. Thanks...