No save button, can’t open design tab, no checkbox to add product in checkout

I was playing around with the free version. I was in the settings when all of the sudden the “Save” button disappeared.

I can no longer open design tab, amongst others.

The upsells in the checkout do not have a checkbox or anything so they can be added to the order.

Please view video here: https://www.loom.com/share/c2f61b9129e94c40b2e732680bba4050

I just purchased the premium version, hoping it would fix the issue.

But it did not!