Your site appears to be blocking the WordPress ajax interface

Hi,
Having activated Easy Digital Downloads, I immediately receive the message “Your site appears to be blocking the WordPress ajax interface”
By clicking the link which references possible solutions, I am working through your recommendations.
Suggestion 1: I deactivated all plugins and the (ajax) message disappeared. I reactivated the EDD plugin only, and the message reappeared immediately.
Suggestion 2: Host Firewall. Here is my hosts response: “We’re not blocking access to admin-ajax.php. We do block loop back connections and by this I mean scripts that request files from themselves using a URL rather than the path. I am not familiar with the plugin you have mentioned but its likely this is the cause to the problem you’re having”
Suggestion 3: Having compared my .htaccess file with the reference you provide, it’s clear that my .htaccess file contains an awful lot more than your illustration. The example you provide is present but it’s right at the bottom / end of my .htaccess file.

So, does the answer from my host clear anything up? and/or should I edit my .htaccess file to match your example, and if so, what would be the impact of stripping out the (significant amount) of preceding rules?
Hope you can help.
Kind regards,

Jeff

https://www.ads-software.com/plugins/easy-digital-downloads-htaccess-editor/