Problem with changing the specifications

[PanenkaPlates]

I am Sander. I added a zip file of a template and was filling in the details of my product on the blank website. At a certain point, when I tried to fill in the specifications, the left sidebar, where the text and options usually appear for editing, kept loading. I have tried several things, but the sidebar continues to load, and I cannot make any changes. Does anyone have a solution? I can make adjustments to all other elements on the site without any issues.