Without so much as a link to your site it’s almost impossible to diagnose. But when I see something line that it’s usually because someone followed directions to password protect the wp-admin directory without carving out an exception for admin-ajax.php, which is WordPress’ preferred way of handling AJAX requests (at least until the REST API matures a bit more).
If that’s the case, this article explains how to set up an exception for the admin-ajax.php file.
Well I did not follow any directions to use what I have known about for years upon years. WordPress on the other hand does not make it very clear as to what a person does once password protecting a directory etc.
I certainly appreciate the link. It did fix it … so far.
And your plugin now works great for anons.
Thumbs up again thanks.