can’t edit

My site is historymapsetc.com
The site shows easily on the web.
When I go to edit my site I have trouble.
I click on a page to edit.
I come to that page and the the Avia layout builder.
Below that the space where the page should show is a spinning grey circle.
It just spins and spins. Nothing happens.
None of my buttons work on this page either.
If I click on help nothing happens.
Any suggestions to fix this problem?
Thank you.
KM