CSS Dynamic Error

after the latest upgrade with WordPress, I am now having an issue with the Nirvana Theme.
When editing or adding a new post I recieve the following error

Failed to load content css: https://canadiansupershop.ca/wp-admin/admin-ajax.php/?action=dynamic_styles

Any idea on how to fit this would be greatly appreciated.
…Bob

• This topic was modified 7 years, 9 months ago by bobwild.