Istio application custom /metrics endpoint stopped collecting new data


With asp .net core application, I implemented custom /metrics endpoint to collect http request count and http request duration. All of a sudden at 6:20am when there should be no one configuration, the metrics endpoint does NOT collect new data. That is you see data in the http response body and it works but the metrics don’t increase. That is, the # of request is still the same number each time I visit the /metrics url. Any ideas or how to troubleshoot?