Recently I have talked to Elastic Cloud support team and they told me that my cluster fails to edit my deployment because I have too many shards in my cluster. They suggested me to delete unused indexes. So I'm doing that right now and I have found many indexes named .reporting-YYYY.MM.DD. When I tried to delete them using the Kibana UI, it told me that those are System Indexes and by deleting them, it could break Kibana. Is it safe to delete them? I think they don't have relevant information.