Cannot create more cloud space

I recently found that I could no longer add images to my library for the campaign I'm running. I was told that I could add more if I deleted some of my current images to free up space. I have deleted upwards of 9 images and over 3 songs (if that's even applicable) and I still keep getting told that I'm out of cloud space after trying to add the same 167 KB png of a zombie-horse. Why is this happening? Is there something I'm doing wrong to free up cloud space? Any help would be appreciated, I really want to be able to add more stuff into my game.

The songs are indeed applicable. If they are of sufficient size, they could gobble up a good portion of your storage. That would be the first place to look if you are trying to winnow down space. Keep in mind that songs need to be deleted from My Audio to make any difference. Simply removing them from a game won't.