I have added a Webhook for all types of events for my REST app in the sandbox environment. My development application logs any requests to a log file, so I can see the data which has been sent. However, PayPal does not send any events when they occur during testing. The Webhooks simulator works and my server does receive mock data, but PayPal does not send any events when I create payments of my own, etc. The Webhooks Events list in the PayPal developer's dashboard is also empty.
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