There seems to be a problem with the Beaver Builder text editor either after the latest WordPress update or TinyMCE Advanced update.
When you choose text-editor it will only show the tabs “Add media”,“Visual” and “Text” and it show the text wrapped in HTML. It doesen’t show the TinyMCE Advanced functions.
The site is in WP Maintenance Mode so i cannot give you a link but I send you screenshots or access to the site.
Here is the website information:
Altitude Pro Theme
Beaver Builder Plugin (Standard Version)