Pages are not allowing edits

Hey there.

I’m trying to edit my site, both live and staging at http://staging.sincere-week.flywheelsites.com and get the same problem in both environments, even after updating plugins in staging and on every page.

The page editor won’t load correctly, so the little wheel keeps spinning incessantly and I can’t edit the pages. See my annotated screenshot below. Last night it spun like that for a couple of hours. Here is a link to a screenshot that shows what it’s doing: https://www.screencast.com/t/Mh9r0GuR

I asked Flywheel, our host, for help, and here is their reply:

“An issue like this is usually either the result of memory exhaustion, a plugin conflict, or a PHP error. I’ve increased the memory limit to mitigate that as a possible cause, but did notice the following error:
`
PHP Fatal error: Uncaught Error: Cannot use string offset as an array in /www/wp-content/themes/enfold/config-templatebuilder/avia-template-builder/php/shortcode-template.class.php:489
`
Usually the solution here would be to re-upload the theme in question, or update it to the latest version (if an update is available). This is very likely the source of the trouble, so you’d want to reach out to the Enfold developers for any further insight if issues persist (I imagine they’ve seen this before and would have a solution for you).”

Any suggestions for me?

Thanks!