Images in Gallery Attachments Opening with No Lightbox – Just Black Page

I am able to add a gallery of images to a product, from the attachments box, and view the images correctly on the product page. But, when I click on an image, it opens the image in the same tab with a black page behind the image. It looks like you’re supposed to close the page to get back to the product – but you need to click the back button.

With the old Jigoshop, when you click on an image, it would open the image, but you could still see the product page behind it, and you just click the “X” on the image to close it. I believe this was a lightbox? I tried editing the image settings, as well as uploading the “Simple Lightbox” plugin, but I can’t get either to make it work. Is there a way to get the lightbox functionality back for these gallery image attachments, so that it looks like on this page with the old Jigoshop? https://simplebeadpatterns.com/product/interwoven/

Thank you,

Cara