3scale APIcast Retry policy not working as expected with POST method

Issue

I have enabled a Retry policy on a particular Product. I set this policy to enabled and the number of retries equal to 3. I then promoted these changes to APIcast-staging. In addition, we set the environment variable APICAST_UPSTREAM_RETRY_CASES with a value of http_500 http_502 http_503 http_504. The Deployment Config YAML file contains the following:

            - name: APICAST_UPSTREAM_RETRY_CASES
              value: http_500 http_502 http_503 http_504

I sent a request to the service with a slightly malformed JSON object in the Body that results in a 500 error response being returned by the backend service. Giving the settings and Retry policy, I expected to see 3 retries of this request to the backend service, however only one request was sent.