Not displaying correctly

Hi there,
For a long time now I’ve not been able to get your plug-in to display in full. It just shows the three buttons. The product details, and even the message “Product was added to your cart” (paraphrasing) does not show. It looks like this:

https://ibb.co/QcrsFPn

It use to show everything else as expected. But stopped doing so some time last year.

In my troubleshooting, I’ve disabled all but 5 plug-ins, to see if there was a conflict. I’ve also switched over to an off-the-shelf Storefront theme. Neither helped.

This is being done on a staging site, that I don’t wish to link to directly as it will get picked up by search engines. Please let me know how I can get a URL through to you, if you’re able to have a look into why it’s not working.

Thanks very much.