ESR uses the http connection (port 80) to MSB to GET/POST data to AAI.
(see OOM configuration https://git.onap.org/oom/tree/kubernetes/esr/charts/esr-server/values.yaml)

msbaddr: msb-iag.{{ include "common.namespace" . }}:80

As MSB removed its http port and only supports https (port 443), ESR is not working.
So implementation changes in OOM and maybe ESR are required.