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Did you try loading the site from a different web browser or device?

Alright, now I see it. It is an strange issue (if it is the first time happening). Did you make any change to the site? (Theme update, plugin update, etc)

Hi, @mattgwilson

This may be a plugin or theme conflict. Please attempt to disable all plugins, and use one of the default (Twenty) themes. If the problem goes away, enable them one by one to identify the source of your troubles.

If you can install plugins, install Health Check Plugin:

https://wordpress.org/plugins/health-check/

On the troubleshooting tab, you can click the button to disable all plugins and change the theme for JUST you, while you’re still logged in, without affecting normal visitors to your site. You can then use its admin bar menu to turn on/off plugins and themes one at a time.

See https://make.wordpress.org/support/handbook/appendix/troubleshooting-using-the-health-check/ for more information.

Hope this helps,
Kind regards.