Nonce failures

I have shared hosting with Krystal (https://krystal.uk/) and use your plugin on all my hosted sites. Some are made with Template Toster (https://templatetoaster.com/) and some are made with Divi (https://www.elegantthemes.com/). The page I have asked for help with is an “example” on a TemplateToaster site – other pages with forms are also failing intermittently. The form plugin on both types of sites is Forminator (https://wordpress.org/plugins/forminator/). Your plugin config is default except for the pages that have forms which have been excluded from cache. However on Divi and Template Toster sites I am getting the error reported from customers: Invalid nonce. Please refresh your browser. This is an intermittent problem but is happening frequently enough to cause problems with customers and site owners. From what I have read on various sites this is a caching problem (lots of references to WP Super Cache) and perhaps config in the htaccess file. I have not yet tried deactivating your plugin or changing the form plugin but before I start on these options I was wondering if you had any advice?
Regards

• This topic was modified 4 years, 6 months ago by Candlelite.

The page I need help with: [log in to see the link]