The failing webhook endpoint is .......

I've been getting notification emails from Stripe regarding webhook endpoint failing.
(https://geneapaths.com/wp-admin/admin-ajax.php?action=psts_stripe_webhook)

"We’ve attempted to notify the endpoint 729 times since June 05 at 12:45PM. If this endpoint is important to your application, please try and fix the issue."

"One recent call to your endpoint returned an HTTP status code 403, However, our webhook systems only treats a webhook as successful if we get back a status code between 200 and 299."