Can’t change logo

I am trying to change the logo in Appearance/Customize/Header/Logo.

When I select the Change Logo button, the Media Library appears. When I select the image and the Select button it goes to “Crop Image” where it just sits with a blank screen. The image never comes up for cropping and all you can do is close the screen.

The same thing happens if you try to change the Site Icon. For both I have tried several different sized files but it doesn’t make a difference. I’ve also tried to “Remove” the existing image first but that doesn’t work either.

Any suggestions?
Kathy