app store server notifications: receiving GET instead of POST

We are attempting to monitor subscription events via App Store Server Notifications. The URL we have configured (with v1 or v2) continually gets invoked with GET requests instead of POST requests, we do not get any POST with request data at all and cannot process subscription changes.

Why might this be happening? What could we have misconfigured?

configuration:

requests:

301/302 redirects do not necessarily preserve POST bodies, and may redirect to GET. We recommend using 307 redirects which guarantee POST is preserved upon redirect

app store server notifications: receiving GET instead of POST
 
 
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