Make sure that your request path in your HealthCheckPolicy configuration is a valid endpoint that returns 200 OK responses or else you will keep getting unhealthy status on your backend service. You can refer to this article for setting up your liveness check. Also, validate that your healthcheck is pointing to the correct port on which your service pod is listening and exposed.

You can also try switching your healthcheck type to HTTP instead of HTTPS and see if it helps.

          config:
            type: HTTP    # Switch to HTTP instead of HTTPS