Images Will Not Load on WooCommerce Product Page

I am trying to add images to new products, but when I click on the Add Product Image, Upload Files, Select Files and then click on the image I want, I am returned to the Select Files page, which is blank. If I click on the Media Library tab, I see a random image and the image I selected is supposedly uploading, but it just sits there and does not load.
this doesn’t happen every time, just enough to be a problem.

Also, sometimes the right side sidebar will flash, making it impossible to select anything to work on. I try reloading the page, same issue.

Any ideas?

The page I need help with: [log in to see the link]