Background transparency irregularities
I have a logo downloaded from Canva as a JPG and as a PNG. Yesterday I was happily removing the background in PS on a macbook and having no issues. Today I'm working from home and editing the same images. I've downloaded them to PS on my iMac and gone to do the same process, unlock layers, magic wand selection , backspace and delete key but nothing happens that I can see! No checkerboard transparency background appears, I'm doing exactly the same procedure on the same files on a different device so can only assume I've got something set differently. Anyone help? I've read all I can find with no results. Image is a PNG, have unlocked the layer, have unchecked contiguously anything I've missed?